Japan Standard Time Group


Transmission of LF standard time and frequency signals from Hagane-yama station will be irregularly suspended for the extension work of the facility.
For more details.(Japanese only)

Welcome to Japan Standard Time (JST) Group. JST Group plays an important role in the Generation, Comparison, and Dissemination of Japan Standard Time and Frequency standard. Please choose the contents you'd like to use.

What's New
What we do
The Information of Standard-time and Frequency-signal Emission (JJY) (The users of radio wave clock see here for more information, please)
Time Dissemination Service (NTP,TEL-JJY,Time Business,calibration)
FAQs and Data

Contact Us

Please contact us if you have any questions, comments, corrections, or suggestions.