Why timestamp conversion matters
Systems rarely agree on one date format. One service returns Unix seconds, another returns milliseconds, and a third emits ISO strings. During debugging, that inconsistency makes otherwise simple questions harder to answer: when did this event happen, has this token expired, and are these logs describing the same moment?
A timestamp converter solves that translation problem by letting you move between machine-friendly and human-friendly values quickly. That is especially helpful in incident review, authentication debugging, integration testing, and support work.
Common formats
| Format | Example | Where it appears |
|---|---|---|
| Unix seconds | 1714761000 | JWT claims, APIs, schedulers |
| Unix milliseconds | 1714761000000 | JavaScript, logs, frontend state |
| ISO string | 2026-05-05T08:30:00Z | APIs, JSON payloads, audit trails |
| Local date/time | 2026-05-05 14:00 | Manual debugging, reporting, support notes |
A simple conversion workflow
- Paste the value exactly as you received it.
- Review Unix seconds, Unix milliseconds, ISO UTC, UTC string, and local time together.
- Use the relative output to confirm whether the value is in the past or future.
- If the timestamp came from a token, compare it with JWT Decoder.
Common mistakes
- Confusing Unix seconds with Unix milliseconds.
- Assuming a local time string is already UTC.
- Reading token expiry without converting the value first.
- Comparing logs from different systems without normalizing time formats.
Related tools
This page pairs especially well with JWT Decoder for exp, iat, and nbf claims, and with the JSON Formatter when timestamps sit inside large payloads. If you are debugging callback flows or signed links, the URL Encoder/Decoder can also help.