About
clocknow API
Every answer says how it was made: meta.error_bound_ms, meta.tzdata_version and meta.server_id. If the server clock has not been measured, the error bound is null rather than a made-up number.
Try it
No key needed for the open endpoints (10,000 requests a month per IP):
curl "https://api.clocknow.net/v1/convert?from=Asia/Karachi&to=America/New_York&time=2026-11-07T12:00"
Get a free key
A key unlocks the astronomy endpoints and gives you your own request counter instead of sharing your IP's.
Already have an account? Manage your keys and passkeys.
curl "https://api.clocknow.net/v1/sun?lat=24.86&lon=67&date=2026-11-07" \ -H "Authorization: Bearer ck_live_…"
Endpoints
| Path | What it returns | Access |
|---|---|---|
/v1/now | Server time for clock sync, optionally with a zone | Open |
/v1/zone | Time, offset, abbreviation and next change in a zone | Open |
/v1/convert | A wall time in one zone shown in another | Open |
/v1/difference | Offset difference between two zones | Open |
/v1/calendar/convert | One date shown in Gregorian, Hijri, Hebrew, Chinese, Persian, Indian, ISO week and Julian Day | Open |
/v1/print/month, /v1/print/year | Printable calendar as a PDF: A4 or Letter, English, Arabic or Urdu, optional Hijri dates | Key |
/v1/signed | Ed25519-signed timestamp you can verify offline | Open |
/v1/sun, /v1/moon, /v1/seasons | Astronomy computed by the same Rust core | Key |
Full reference: openapi.json (OpenAPI 3.1; import it into Postman, Insomnia or a client generator).
Limits
Requests are counted per calendar month (UTC). Past the limit you get 429 with Retry-After in seconds; X-RateLimit-Limit, X-RateLimit-Remaining and X-RateLimit-Reset are on every response. Paid tiers with higher limits are not open yet.
Please credit clocknow.net when you show our data to your users.