Services
Seven services that make experiences simpler through technology
Guided by our mission, "Make people's experiences simpler and more comfortable through technology," Teraren provides a range of API services that developers and businesses can use free of charge.
Since launching in 2015, our APIs have been completely free and unlimited, and are used by many developers and companies. We believe the basic data infrastructure people need every day, such as postal code lookup, financial institution codes, and station and railway information, should be freely available to everyone.
No API key. No authentication. No rate limits. We take care of the infrastructure so developers can focus on building services that truly matter.
Our Services
From developer APIs to specialist blogs, we serve a wide range of needs.
Post-kun
postcode.teraren.comA postal code lookup API covering all of Japan. Free, unlimited, and fast (about 70 ms per response). Reliably operated since 2015. Useful everywhere, from address autofill on e-commerce sites to delivery management systems and regional analysis tools.
- Completely free, unlimited access
- Fast responses (about 70 ms)
- Nationwide coverage
- Served via Cloudflare CDN
Bank-kun
bank.teraren.comA financial institution code lookup API. Search bank and branch codes free and without limits, with data regularly updated from the National Tax Agency. Instantly get the bank code information needed for accounting systems, payroll transfers, financial apps, and other transactions.
- Completely free, unlimited access
- Covers all financial institutions
- Bank and branch code search
- National Tax Agency data integration
Station & Railway API
train.teraren.comA railway and station information API with detailed data on 174 operators, 10,937 stations, and 622 lines, including latitude and longitude. Ideal for building services on station data, such as real estate sites, commuting expense tools, and local information apps.
- 174 railway operators
- Details for 10,937 stations
- Data for 622 lines
- Latitude and longitude included
Gengo-kun
seireki.teraren.comA converter between Japanese era years and Western calendar years. Easily convert era names and look up public holidays and zodiac signs.
- Japanese era ⇔ Western year conversion
- Public holiday lookup
- Chinese zodiac display
- Simple and easy to use
Corporate Number Search API
corporation.teraren.comAn API for searching corporate numbers and qualified invoice issuer registration numbers. Covers all 47 prefectures and also provides EDINET financial disclosure data.
- Corporate number search
- Qualified invoice number search
- All 47 prefectures
- EDINET financial disclosure data
AI TRI+
ai-triathlon-result.teraren.comAI-powered triathlon training plans and race result analysis. Automatically generates a fully personalized training plan from over 100 data points. Level up efficiently with 24/7 AI coaching.
- AI training plan generation
- 24/7 AI coaching
- Race result analysis
- Data visualization
An IT Engineer's Triathlon Diary
triathlon.teraren.comA personal blog about triathlon training, pursuing better performance with a focus on value for money.
- Training logs
- Cost-effective gear choices
- Written for IT engineers
- Tips for balancing training and work
Swift Sport Custom Diary
zc33s.teraren.comA customization blog for the ZC33S Suzuki Swift Sport, sharing expertise on car maintenance and modification. Supports push notifications.
- ZC33S-specific information
- Customization know-how
- Maintenance records
- Push notifications
Questions or Requests About Our Services
Whether you have a question about a service or a feature request,
please feel free to contact us.