Japan
Opensignal is the independent global standard for analyzing consumers' connectivity experiences. Our industry reports are the definitive guide to understanding what happens when people use their mobile and broadband connections in their daily life.
Japan
Opensignal is the independent global standard for analyzing consumers' connectivity experiences. Our industry reports are the definitive guide to understanding what happens when people use their mobile and broadband connections in their daily life.
Key Findings
au keeps Consistent Quality and Reliability Experience in Japan
Once again, au wins both the Consistent Quality and Reliability Experience awards outright. It claims Reliability Experience for the fourth consecutive time, with a score of 967 points on a 100–1000 point scale. au also remains the sole winner of Consistent Quality, scoring 88.3% and beating SoftBank by one percentage point.
SoftBank retains Download Speed Experience and Time on 5G
Opensignal users on SoftBank’s network enjoy 17% faster download speeds since the previous report. The speed boost reinforces SoftBank’s lead in Download Speed Experience. SoftBank is also the sole winner of the Time on 5G award, with a score of 27.4%. This metric reflects how often users are actively connected to a 5G network bearer.
NTT docomo has the widest geographic coverage footprint across Japan
NTT docomo retains both the Coverage Experience and 5G Coverage Experience awards, boasting the widest and most extensive geographic coverage footprint in populated areas among Japan’s mobile operators across both overall and 5G networks.
au achieves a clean sweep for experiential awards in Japan
au breaks out of a statistical tie with SoftBank seen in the previous report and ends with a sole win for Video Experience in this report, with a score of 74.1 points on a 100-point scale. This means au is the sole winner across all experiential awards — Video Experience, Live Video Experience, Games Experience and Voice App Experience — for both overall and 5G metrics.
Rakuten Mobile continues to improve its 5G performance
Rakuten Mobile has seen improvements in its 5G coverage and experiential metrics compared to the previous report, thanks to its ongoing investment in mobile infrastructure in Japan.
au collects the most awards across Japanese regions
au leads the regional award count in Japan — with 45 outright wins and 46 shared awards across eight regions. It achieves a clean sweep in both Games Experience and 5G Games Experience. Other Japanese MNOs mirror this performance in their respective categories across the regions — Rakuten Mobile wins outright in all eight regions for Upload Speed Experience and 5G Upload Speed, and SoftBank in Time on 5G.
Mobile Experience Awards
Market Overview
In Opensignal's latest Japan Mobile Network Experience report, au leads the national award count with ten sole and one joint win. It achieves a clean sweep for experiential awards in Japan, while also winning Consistent Quality and Reliability Experience outright.
NTT docomo retains all of its awards from the previous report. Rakuten Mobile and SoftBank each win two awards — Rakuten Mobile leads in upload speeds (overall and 5G), while SoftBank retains Download Speed Experience and Time on 5G.
Japanese operators also performed strongly in Opensignal’s recent Global Awards report. au, Rakuten Mobile and SoftBank are among Global Winners for Time on 4G/5G in the large land area category, while au is also named a Global Winner for Games Experience, Reliability Experience and Voice App Experience. SoftBank is among Global Leaders in five categories, au in two, while NTT docomo and Rakuten Mobile — in one each.
Japan’s operators continue to expand 5G capabilities. Rakuten Mobile has announced that Nokia's cloud-native network functions are now live in commercial production on the Rakuten Cloud, supporting Rakuten Mobile’s 4G and 5G services with enhanced automation and improved network resilience. Nokia is also collaborating with SoftBank to upgrade the operator’s current network and expand its 5G Standalone (SA) coverage across Western Japan. Meanwhile, Japan’s Ministry of Internal Affairs and Communications has opened applications for 26GHz, marking a significant step in the nationwide expansion of mmWave 5G services, with the auction scheduled for later in 2026.
NTT docomo has commenced the live deployment of Ericsson’s AIR 3255 Massive MIMO antenna-integrated radios across its 5G network, using the 4.5GHz spectrum band, to alleviate congestion in high-traffic urban areas. While NTT docomo continues its 5G deployments, it has also officially terminated its 3G services on the last day of March 2026, marking the end of the 3G era in Japan. While other Japanese operators shut down their 3G networks earlier, NTT docomo’s market leadership came with a heavier social burden, with 350,000 customers still relying on 3G services, partly due to their loyalty to “garakei” feature flip phones — devices that are simple and familiar for older generations but do not support newer network generations.
All of Japan’s major MNOs have launched a nationwide emergency roaming service — “JAPAN Roaming” — effective 1 April 2026. Aimed at improving disaster resilience in a seismically active country, it allows users to temporarily connect to another operator’s 4G LTE network if their primary provider suffers major outages due to natural disasters. The initiative is limited to catastrophic events and does not cover localized disruptions or network maintenance. Separately, MNOs are also developing direct-to-cell (D2C) satellite services, which would allow standard smartphones to connect directly to satellites to provide coverage in remote areas where conventional mobile infrastructure is unavailable. NTT docomo and SoftBank are partnering with Starlink, while Rakuten Mobile is partnering with AST SpaceMobile. Meanwhile, au announced the kickoff of international roaming service for its au Starlink Direct services for subscribers travelling to the U.S. This marks the world's first cross-border connectivity using direct satellite-to-smartphone service.
In this report, we examine the mobile network experience of the four main mobile network operators in Japan — au, NTT docomo, Rakuten Mobile and SoftBank — over a period of 90 days starting on January 1, 2026, and ending on March 31, 2026, to see how they fared.
Opensignal reports include main brand experience only; sub-brands are not included. However, NTT docomo's other price plans (eximo, ahamo & irumo) are included in its scores. Our metrics include all user measurements reported across all mobile technologies, including when users have exceeded their data allowance — and NTT docomo’s data includes 3G, as data collection took place before NTT docomo shut down its 3G network.
Overall Experience
National Analysis
au breaks out of the statistical tie it shared with SoftBank in the previous report and claims the win outright in this report, with a score of 74.1 points on a 100-point scale. It beats SoftBank, the previous joint winner, by less than one point. NTT docomo and Rakuten Mobile are statistically tied for third place, with scores of 70.9–71.1 points.
All Japanese operators rate as Very Good (68–78) for the overall video streaming experience on mobile devices. This means our users are, on average, able to stream video at 1080p or better, with satisfactory loading times and minimal stalling.
Video Experience scores account for adaptive bitrate streaming (ABR), a technology that allows Opensignal to accurately represent users' real video experience, including video streams up to 4K quality.
Definitions
Opensignal’s Video Experience quantifies the quality of video streamed to mobile devices by measuring real-world video streams over an operator's networks. The metric is based on an International Telecommunication Union (ITU) approach, built upon detailed studies which have derived a relationship between technical parameters, including picture quality, video loading time and stall rate, with the perceived video experience as reported by real people. To calculate video experience, we are directly measuring video streams from end-user devices and using this ITU approach to quantify the overall video experience for each operator on a scale from 0 to 100. The videos tested include a mixture of resolutions — including Full HD (FHD) and 4K / Ultra HD (UHD) — and are streamed directly from the world’s largest video content providers.
In addition to Video Experience, we report on the following metrics related to video experience:
- 5G Video Experience: The average Video Experience of Opensignal users when they were connected to an operator’s 5G network.
- Video Experience – 5G Users: The average Video Experience of Opensignal users with a 5G device and a 5G subscription across an operator's networks. It factors in 2G, 3G, 4G and 5G video experience along with the availability of each technology.
- 4G Video Experience: The average Video Experience of Opensignal users on an operator's 4G network.
- 3G Video Experience: The average Video Experience of Opensignal users on an operator’s 3G network.
National Analysis
Once again, au wins the Live Video Experience award outright, with a score of 70.5 points on a 100-point scale — one point ahead of SoftBank.
All operators place in the Excellent (58 or above) category, meaning that our users are, on average, able to stream video at least at 1080p with low loading times, little stalling and a satisfactory live offset.
Operators’ Live Video Experience scores are determined using measures that affect perceived live streaming viewing experience, including picture quality, video loading time, stall rate and live playback offset — the time difference between real time and the playback position a viewer sees. Unlike Video Experience, which represents on-demand video streams, Live Video Experience quantifies live streaming for current events such as live sports, game streams, music concerts or news as they happen.
Definitions
Opensignal’s Live Video Experience quantifies the quality of real-time video streamed to mobile devices by measuring video streams over an operator's network. The metric extends the existing International Telecommunication Union (ITU) approach used for Opensignal's on-demand Video Experience metric, built upon detailed studies which have derived a relationship between technical parameters, including live playback offset, picture quality, video loading time and stall rate, with the perceived live video experience as reported by real people. To calculate live video experience, we are directly measuring live video streams from end-user devices and using this extension of ITU's approach to quantify the overall live video experience for each operator on a scale from 0 to 100. The videos tested include a mixture of resolutions and are streamed directly from the world’s largest video content providers.
National Analysis
au retains the Games Experience award with a score of 88.2 points on a 100-point scale, two points ahead of SoftBank.
SoftBank and au are rated Excellent (85 or above), while Rakuten Mobile and NTT docomo are one category lower, in Good (75–85). An Excellent rating means the vast majority of users deem the network experience acceptable, with nearly all users feeling in control of the game and receiving immediate feedback on their actions, with no noticeable delay in almost all cases.
Definitions
Opensignal’s Games Experience measures how mobile users experience real-time multiplayer mobile gaming on an operator’s network. Measured on a scale of 0-100, it analyzes how our users’ multiplayer mobile gaming experience is affected by mobile network conditions including latency, packet loss and jitter.
Games Experience quantifies the experience when playing real-time multiplayer mobile games on mobile devices connected to servers located around the world. The approach is built on several years of research quantifying the relationship between technical network parameters and the gaming experience as reported by real mobile users. These parameters include latency (round trip time), jitter (variability of latency) and packet loss (the proportion of data packets that never reach their destination). Additionally, it considers multiple genres of multiplayer mobile games to measure the average sensitivity to network conditions. The games tested include some of the most popular real-time multiplayer mobile games (such as Fortnite, Pro Evolution Soccer and Arena of Valor) played around the world.
Calculating Games Experience starts with measuring the end-to-end experience from users’ devices to internet end-points that host real games. The score is then measured on a scale from 0 to 100.
In addition to Games Experience, we report on the following metrics related to games experience:
- 5G Games Experience: The average Games Experience of Opensignal users when they were connected to an operator’s 5G network.
- Games Experience – 5G Users: The average Games Experience of Opensignal users with a 5G device and a 5G subscription across an operator's networks. It factors in 2G, 3G, 4G and 5G games experience along with the availability of each technology.
- 4G Games Experience: The average Games Experience of Opensignal users on an operator's 4G network.
- 3G Games Experience: The average Games Experience of Opensignal users on an operator's 3G (e.g. UMTS/HSPA or CDMA 1X EV-DO) network.
National Analysis
au remains the sole winner of the Voice App Experience award, with a score of 84.5 points on a 100-point scale.
Regardless of their choice of operator, our Japanese users experience Good (80–87) quality of voice app services. This means many users are satisfied, though some experience minor quality impairments, such as background noise that is sometimes not quite clear — either hazy or not loud enough — while clicking sounds or distortion are very rarely present.
Definitions
Opensignal's Voice App Experience measures the quality of experience for over-the-top (OTT) voice services — mobile voice apps such as WhatsApp, Skype and Facebook Messenger — using a model derived from the International Telecommunication Union (ITU) approach for quantifying overall voice call quality and a series of calibrated technical parameters. This model characterizes the exact relationship between the technical measurements and perceived call quality. Voice App Experience for each operator is calculated on a scale from 0 to 100.
In addition to Voice App Experience, we report on the following metrics related to voice app experience:
- 5G Voice App Experience: The average Voice App Experience of Opensignal users when they were connected to an operator’s 5G network.
- Voice App Experience – 5G Users: The average Voice App Experience of Opensignal users with a 5G device and a 5G subscription across an operator's networks. It factors in 2G, 3G, 4G and 5G voice app experience along with the availability of each technology.
- 4G Voice App Experience: The average Voice App Experience of Opensignal users on an operator's 4G network.
- 3G Voice App Experience: The average Voice App Experience of Opensignal users on an operator's 3G (e.g. UMTS/HSPA or CDMA 1X EV-DO) network.
National Analysis
Our users on SoftBank’s network continue to enjoy the fastest overall download speeds, clocking in at 65.1Mbps, following an impressive 17% increase in Download Speed Experience.
Definitions
Measured in Mbps, Download Speed Experience represents the typical everyday speeds a user experiences across an operator’s mobile data networks.
In addition to Download Speed Experience, we report on the following metrics related to download speeds:
- 5G Download Speed: The average download speed observed by Opensignal users with active 5G connections.
- Download Speed Experience – 5G Users: The average download speeds experienced by Opensignal users with a 5G device and a 5G subscription across an operator’s networks. It factors in 2G, 3G, 4G, and 5G download speeds along with the availability of each technology.
- 4G Download Speed: The average downlink speed observed by Opensignal users when they were connected to 4G.
- 3G Download Speed: The average downlink speed observed by Opensignal users when they were connected to 3G (e.g. UMTS/HSPA or CDMA 1X EV-DO).
National Analysis
Rakuten Mobile reaffirms its dominance in Upload Speed Experience, winning once again with a score of 15.8Mbps and an impressive 7Mbps lead over runner-up SoftBank.
Definitions
Upload Speed Experience measures the average upload speeds for each operator observed by our users across their mobile data networks. Typically upload speeds are slower than download speeds, as current mobile broadband technologies focus resources on providing the best possible download speed for users consuming content on their devices. As mobile internet trends move away from downloading content to creating content and supporting real-time communications services, upload speeds are becoming more vital and new technologies are emerging that boost upstream capacity.
In addition to Upload Speed Experience, we report on five supporting metrics related to upload speeds:
- 5G Upload Speed: The average upload speed observed by Opensignal users with active 5G connections.
- Upload Speed Experience – 5G Users: The average upload speeds experienced by Opensignal users with a 5G device and a 5G subscription across an operator’s networks. It factors in 2G, 3G, 4G, and 5G upload speeds along with the availability of each technology.
- 4G Upload Speed: The average uplink speed observed by Opensignal users when they were connected to 4G.
- 3G Upload Speed: The average uplink speed observed by Opensignal users when they were connected to 3G (e.g. UMTS/HSPA or CDMA 1X EV-DO).
Regional Analysis
Regional Analysis Summary: Japan, Mobile Network Experience Report, April 2026
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A-I
- Chubu
- Chugoku
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- Kanto
- Kinki
- Kyushu
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- Shikoku
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5G Experience
National Analysis
au maintains a firm lead in 5G Video Experience, winning the award with a score of 77.4 points on a 100-point scale.
All operators fall into the Very Good (68–78) category, meaning that our users are, on average, able to stream video at 1080p or better with satisfactory loading times and minimal stalling.
5G Video Experience scores account for adaptive bitrate streaming (ABR), a technology that allows Opensignal to accurately represent users' real video experience, including video streams up to 4K quality.
Definitions
5G Video Experience quantifies the quality of mobile video experienced by Opensignal users on real-world video streams when they were connected to 5G. The metric is based on an International Telecommunication Union (ITU) approach, built upon detailed studies which have derived a relationship between technical parameters, including picture quality, video loading time and stall rate, with the perceived video experience as reported by real people. To calculate 5G Video Experience, we are directly measuring video streams from end-user devices and using this ITU approach to quantify the video experience observed by our users on each operator’s 5G network on a scale from 0 to 100. The videos tested include a mixture of resolutions — including Full HD (FHD) and 4K / Ultra HD (UHD) — and are streamed directly from the world’s largest video content providers.
National Analysis
au successfully defends the 5G Live Video Experience award, with a score of 74.4 points on a 100-point scale.
All operators place in the Excellent (58 or above) category, meaning users are, on average, able to stream live video at least at 1080p with low loading times, little stalling and a satisfactory live offset.
Operators’ 5G Live Video Experience scores are determined using measures that affect perceived live streaming quality, including picture quality, video loading time, stall rate and live playback offset — the time difference between real time and the playback position viewers see. Unlike 5G Video Experience, which reflects on-demand streams, 5G Live Video Experience quantifies live streaming for current events such as live sports, game streams, music concerts or news.
Definitions
Opensignal’s Live Video Experience quantifies the quality of real-time video streamed to mobile devices by measuring video streams over an operator's network. The metric extends the existing International Telecommunication Union (ITU) approach used for Opensignal's on-demand Video Experience metric, built upon detailed studies which have derived a relationship between technical parameters, including live playback offset, picture quality, video loading time and stall rate, with the perceived live video experience as reported by real people. To calculate live video experience, we are directly measuring live video streams from end-user devices and using this extension of ITU's approach to quantify the overall live video experience for each operator on a scale from 0 to 100. The videos tested include a mixture of resolutions and are streamed directly from the world’s largest video content providers.
5G Live Video Experience quantifies the quality of mobile video experienced by Opensignal users on real-world live video streams when they were connected to 5G.
National Analysis
au retains the 5G Games Experience award with a score of 92.7 points on a 100-point scale — two points ahead of runner-up SoftBank.
NTT docomo, SoftBank and au rate as Excellent (85 or above), while Rakuten Mobile is one category lower, rated Good (75–85). An Excellent rating means the vast majority of users deem the experience acceptable, with nearly all users feeling in control and receiving immediate feedback, with no noticeable delay in almost all cases.
Definitions
5G Games Experience measures how mobile users experience real-time multiplayer mobile gaming on an operator's 5G network. It analyzes how our users’ multiplayer mobile gaming experience was affected by mobile network conditions including latency, packet loss and jitter. 5G Games Experience for each operator is calculated on a scale from 0 to 100.
5G Games Experience quantifies the experience when playing real-time multiplayer mobile games on mobile devices connected to servers located around the world. The approach is built on several years of research quantifying the relationship between technical network parameters and the gaming experience as reported by real mobile users. These parameters include latency (round trip time), jitter (variability of latency) and packet loss (the proportion of data packets that never reach their destination). Additionally, it considers multiple genres of multiplayer mobile games to measure the average sensitivity to network conditions. The games tested include some of the most popular real-time multiplayer mobile games (such as Fortnite, Pro Evolution Soccer and Arena of Valor) played around the world. Calculating 5G Games Experience starts with measuring the end-to-end experience from users’ devices to internet end-points that host real games.
National Analysis
Once again, au wins the 5G Voice App Experience award outright — this time with a score of 85.6 points on a 100-point scale — narrowly ahead of second-placed SoftBank.
All operators achieve a Good (80–87) rating for 5G Voice App Experience. This means many users are satisfied, though some experience minor quality impairments — for example, occasional clicking sounds or slight distortion.
Definitions
5G Voice App Experience quantifies the experience of Opensignal users when using over-the-top voice apps — such as WhatsApp, Skype and Facebook Messenger — on an operator’s 5G network. It uses a model derived from the International Telecommunication Union (ITU) approach for quantifying overall voice call quality and a series of calibrated technical parameters. This model characterizes the exact relationship between the technical measurements and perceived call quality. 5G Voice App Experience for each operator is calculated on a scale from 0 to 100.
National Analysis
NTT docomo confirms its leadership in 5G Download Speed, winning the award outright with a score of 159.1Mbps and a lead of around 9Mbps over statistically tied au and SoftBank.
Definitions
5G Download Speed shows the average download speed experienced by Opensignal users across an operator’s 5G network. 5G Download Speed for each operator is calculated in Mbps (Megabits per second).
National Analysis
Rakuten Mobile remains the sole winner of the 5G Upload Speed award with a score of 23.8Mbps. This is 50% faster than what our users experience on au and SoftBank’s networks, as both operators record identical scores of 15.8Mbps.
Definitions
5G Upload Speed measures the average upload speeds experienced by Opensignal users across an operator’s 5G network. 5G Upload Speed for each operator is calculated in Mbps (Megabits per second).
Regional Analysis
Regional Analysis Summary: Japan, Mobile Network Experience Report, April 2026
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- Chubu
- Chugoku
- Hokkaido
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- Kinki
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Coverage
National Analysis
NTT docomo once again triumphs in Coverage Experience, with a score of nine points on a 10-point scale — one point ahead of au. This score indicates that NTT docomo has the widest and most extensive geographic coverage footprint in populated areas among Japan’s mobile operators.
Definitions
The Opensignal Coverage Experience metric measures the extent of mobile networks in the places people live, work and travel. The metric represents the experience users receive as they travel around areas where they would reasonably expect to find coverage.
Traditional coverage metrics typically estimate either a percentage of land area covered, or a percentage of population covered; often neither will be an accurate measurement of the true user expectation and experience. In many markets there are areas where neither population density nor geographic area reflect the importance of coverage to users. For example, in a large mountain range most users will not expect coverage in the wilderness, but poor coverage in the relatively small area of a ski resort is critical for the enjoyment of a holiday. Estimates based purely on population give undue significance to coverage in the most densely populated areas.
Coverage Experience measures geographic coverage of populated areas and therefore more accurately reflects the coverage expectations and experience of typical users. It can give a result that is somewhat different to traditional estimates based on either geographic or population measures. The metric uses a scale from 0 to 10.
National Analysis
NTT docomo retains the 5G Coverage Experience award with a score of five points on a 10-point scale, one point ahead of au. This score indicates that NTT docomo has the widest and most extensive geographic 5G coverage footprint in populated areas among Japan’s mobile operators.
Definitions
The Opensignal Coverage Experience metric measures the extent of mobile networks in the places people live, work and travel. The metric represents the experience users receive as they travel around areas where they would reasonably expect to find coverage.
Traditional coverage metrics typically estimate either a percentage of land area covered, or a percentage of population covered; often neither will be an accurate measurement of the true user expectation and experience. In many markets there are areas where neither population density nor geographic area reflect the importance of coverage to users. For example, in a large mountain range most users will not expect coverage in the wilderness, but poor coverage in the relatively small area of a ski resort is critical for the enjoyment of a holiday. Estimates based purely on population give undue significance to coverage in the most densely populated areas.
Coverage Experience measures geographic coverage of populated areas and therefore more accurately reflects the coverage expectations and experience of typical users. It can give a result that is somewhat different to traditional estimates based on either geographic or population measures. The metric uses a scale from 0 to 10.
5G Coverage Experience shows the proportion of places Opensignal users with a 5G device and a 5G subscription had an active 5G connection.
National Analysis
NTT docomo and au remain joint winners of Time on Network, with identical scores of 99.7%. These figures represent the proportion of time Opensignal users spend with a 5G, 4G or 3G mobile signal.
Prior to Q4 2025, Time on Network was referred to as Availability in Opensignal reports.
Definitions
Our time on network and availability metrics are not measures of a network’s geographical extent. They won’t tell you whether you are likely to get a signal if you plan to visit a remote rural or nearly uninhabited region. Instead, they measure what proportion of time people have a network connection, in the places they most commonly frequent — something often missed by traditional coverage metrics. Looking at when users have a connection rather than where, provides us with a more precise reflection of the true user experience.
We also keep track of the instances that leave mobile users most frustrated: when there is no signal to connect to at all. The most common dead zones users struggle with occur indoors. As most of our time on network data is collected indoors (as that’s where users spend most of their time), we’re particularly astute at detecting areas of zero signal.
Our time on network and availability metrics take a user-centric, time-based approach that complements the user-centric and geographical-based methodology used by our reach metrics.
Time on Network shows the proportion of time all Opensignal users on an operator’s network had either a 3G, 4G or 5G connection.
National Analysis
SoftBank wins Time on 5G outright with a score of 27.4%, eight percentage points ahead of au.
Time on 5G measures the percentage of time users with a 5G device are actively connected to a 5G network bearer, indicating how often data traffic is carried over 5G rather than 4G. Prior to Q4 2025, Time on 5G was referred to as 5G Availability in Opensignal reports.
Definitions
Our time on network and availability metrics are not measures of a network’s geographical extent. They won’t tell you whether you are likely to get a signal if you plan to visit a remote rural or nearly uninhabited region. Instead, they measure what proportion of time people have a network connection, in the places they most commonly frequent — something often missed by traditional coverage metrics. Looking at when users have a connection rather than where, provides us with a more precise reflection of the true user experience.
We also keep track of the instances that leave mobile users most frustrated: when there is no signal to connect to at all. The most common dead zones users struggle with occur indoors. As most of our time on network data is collected indoors (as that’s where users spend most of their time), we’re particularly astute at detecting areas of zero signal.
Our time on network and availability metrics take a user-centric, time-based approach that complements the user-centric and geographical-based methodology used by our reach metrics.
Time on 5G shows the proportion of time Opensignal users with a 5G device and a 5G subscription utilised an active 5G connection.
Regional Analysis
Regional Analysis Summary: Japan, Mobile Network Experience Report, April 2026
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- Chubu
- Chugoku
- Hokkaido
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J-R
- Kanto
- Kinki
- Kyushu
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S-Z
- Shikoku
- Tohoku
in Chubu
in Chubu
in Chugoku
in Chugoku
in Hokkaido
in Hokkaido
in Kanto
in Kanto
in Kinki
in Kinki
in Kyushu
in Kyushu
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Consistency
National Analysis
au remains the sole winner of Consistent Quality, with a score of 88.3%, beating SoftBank by one percentage point.
This metric measures whether the network is sufficient to support common mobile application requirements at a level that is ‘good enough’ for users to complete typical demanding tasks on their devices. It assesses experience indicators including download throughput, upload throughput, latency, jitter, packet loss and time to first byte.
Definitions
Consistent Quality measures if the network is sufficient to support common mobile application requirements at a level that is ‘good enough’ for users to maintain (or complete) various typical tasks on their devices.
We combine different experience indicators such as download throughput, upload throughput, latency, jitter, packet discard, and time to first byte to calculate Consistent Quality. These components are evaluated against thresholds recommended by various more demanding common applications used for a range of common tasks.
To calculate the metric value, the proportion of tests that pass the requirements of Consistent Quality is multiplied by the test success ratio, which is the proportion of completed tests to all tests conducted. Tests that pass indicate that activities such as video calling, uploading an image to social media, or using smart home applications will be possible without noticeable lag or slowdown.
National Analysis
au takes first place for Reliability Experience, scoring 967 points on a 100–1000 point scale. SoftBank comes second, only five points behind the winner.
Opensignal’s Reliability Experience measures the ability of our users to connect to and successfully complete basic tasks on operators’ networks. It consists of the following components:
a) Signal Availability — the proportion of time Opensignal users can successfully receive a mobile network signal,
b) Data Connectivity — the proportion of time when the network is available and the device can connect to the internet,
c) Task Completion — whether tasks initiated by the user’s device are completed,
d) Sufficiency — the probability that (basic) tasks will be executed sufficiently well for the user.
Definitions
Opensignal’s Reliability Experience measures the ability of Opensignal users to connect to and successfully complete (basic) tasks on communication service providers’ (CSP) networks. It analyzes how much Opensignal users’ experience is affected by the radio access and core network, along with issues that prevent them from connecting to the internet even if they have a connection to their CSP’s network. It also factors in users’ ability to successfully use lower performance applications including SD video, over-the-top voice calls and web browsing.
Regional Analysis
Regional Analysis Summary: Japan, Mobile Network Experience Report, April 2026
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J-R
- Kanto
- Kinki
- Kyushu
-
S-Z
- Shikoku
- Tohoku
in Chubu
in Chubu
in Chugoku
in Chugoku
in Hokkaido
in Hokkaido
in Kanto
in Kanto
in Kinki
in Kinki
in Kyushu
in Kyushu
in Shikoku
in Shikoku
in Tohoku
in Tohoku
Related Analysis
Our Methodology
Collecting billions of individual measurements daily from over 100 million devices globally, Opensignal independently analyzes mobile and broadband user experience on every major network operator around the globe.
About Opensignal
Opensignal is the leading global provider of independent insights into consumers' connectivity experiences and choice of carrier. Our proprietary insights into mobile and broadband networks give operators the solutions they need to profitably compete and win, from executive level scorecards and public validation to pin-point level engineering analytics and consumer decision dynamics.
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Confidence Intervals
For every metric we calculate statistical confidence intervals indicated on our graphs. When confidence intervals overlap, our measured results are too close to declare a winner. In those cases, we show a statistical draw. For this reason, some metrics have multiple operator winners.
In our bar graphs we represent confidence intervals as boundaries on either sides of graph bars.
In our supporting-metric charts we show confidence intervals as +/- numerical values.
Why confidence intervals are vital in analyzing mobile network experience