Monthly Report: December 2025
Jan 6, 2026
Monthly Report of Sauna Facility Rankings
We report the December sauna facility rankings based on 'T-Flow Scores' utilizing measurement data from the sauna device.
Factors of Monthly Ranking Fluctuations
Monthly rankings of sauna facilities fluctuate due to various factors. Since changes in seasons and weather alter the number of sauna users and comfort levels, these impacts are reflected in the rankings.
In addition, improvements to the facilities themselves and hosting events are also factors that influence the rankings. Therefore, the rankings are updated monthly, allowing everyone who uses 'Sanokuni' to always get the latest information.
Nationwide T-Flow Score Rankings
| Ran k | Facility Name | Prefec ture | T-Flow Score |
|---|---|---|---|
| 1 | SAUNA JAPON | Tokyo | 87.85 |
| 2 | Sauna Kisarazu Tsuboya | Chiba | 87.59 |
| 3 | Sauna F-Tuuli | Fukushima | 87.06 |
| 4 | Sauna&Drink YOQ | Tokyo | 87.04 |
| 5 | East Land | Tokyo | 86.66 |
| 6 | Tsukuba Onsen Kirari Bettei | Ibaraki | 86.65 |
| 7 | Natural Hot Spring Korona no Yu Fukuyama | Hiroshima | 86.59 |
| 8 | Genjii no Mori Onsen | Fukuoka | 86.58 |
| 9 | Hitachinaka Onsen Kirari Bettei | Ibaraki | 86.57 |
| 10 | Ryusenji no Yu Toyota Josui | Aichi | 86.38 |
Attention Ranking
The rate of increase in users compared to the previous month is defined as 'Attention'!
| Ra nk | Facility Name | Pref ecture | Attention |
|---|---|---|---|
| 1 | Higashidogo no Soratomori | Ehime Prefecture | 560% |
| 2 | Ofuro Cafe Rinne no Yu | Ibaraki Prefecture | 500% |
| 3 | YUBUNE SAUNA PARK | Saitama Prefecture | 335% |
| 4 | Holiday Sports Club Owariasahi | Aichi Prefecture | 300% |
| 5 | Kanazawa Yumenoyu | Ishikawa Prefecture | 289% |
| 6 | Urban Spa | Kanagawa Prefecture | 225% |
| 7 | Mizusawa Onsenkan | Yamagata Prefecture | 214% |
| 8 | Premier Hotel -CABIN- Sapporo | Hokkaido | 200% |
| 9 | Natural Hot Spring Kachofugetsu | Saitama Prefecture | 200% |
| 10 | Natural Hot Spring Hotel Komachi | Akita Prefecture | 200% |
T-Flow Score Growth Rate Ranking
Calculating the average T-Flow Score growth rate for each facility compared to the previous month!
| Ra nk | Facility Name | Prefec ture | Increase Rate |
|---|---|---|---|
| 1 | Healthy Onsen Sakuragawa | Osaka Prefecture | +22.00% |
| 2 | Yunosato Setogawa Onsen | Okayama Prefecture | +20.17% |
| 3 | Yokote Ekimae Onsen Yuyu Plaza | Akita Prefecture | +20.02% |
| 4 | Holiday Sports Club Ube | Yamaguchi Prefecture | +18.41% |
| 5 | Ekichika Onsen Kuroshio | Shizuoka Prefecture | +17.77% |
| 6 | Hinatayama Onsen Hananoyu | Kagoshima Prefecture | +16.52% |
| 7 | Konami Sports Club Musashikosugi | Kanagawa Prefecture | +15.01% |
| 8 | Yutorion Taiyu | Akita Prefecture | +14.88% |
| 9 | Wakamatsuyu | Kyoto Prefecture | +14.21% |
| 10 | Natural Onsen Elm no Yu | Aomori Prefecture | +13.91% |
Significance of Monthly Rankings
The monthly rankings compiled using the "T-Flow Score" are a highly useful source of information for sauna enthusiasts.
The rankings are evaluated objectively and fairly based on data from sauna devices. This allows these rankings to be used as a new metric that incorporates the comfort, invigoration, and safety of sauna sessions.
Calculation Method
Attention Level: Based on registered Totonoi Log data, it displays the growth rate of the number of Facility users compared to the previous month. For example, 250% means the number of users increased by 2.5 times (i.e., a 150% increase) compared to the previous month.
Average T-Flow Score Growth Rate: It displays the rate of change in the average T-Flow Score at each Facility compared to the previous month. For example, +25.2% means the average T-Flow Score increased by 25.2% compared to the previous month.
This concludes the Monthly Report for December.
Have a great sauna life this month as well!
