- Timestamp to date: paste a Unix timestamp into the input. The tool detects whether it is in seconds or milliseconds and displays the matching date and time.
- The result shows local time, UTC and ISO 8601, plus a relative value such as “3 hours ago” or “in 2 days”.
- Date to timestamp: pick a date and time, then press Convert to timestamp to get the numeric value in the Seconds or Milliseconds unit you select.
A Unix timestamp is the number of seconds (or milliseconds) elapsed since January 1, 1970 UTC. Because the tool distinguishes the two units automatically, you avoid the classic mistake of interpreting a millisecond value as seconds and getting a date in the far future.
All conversion runs locally in your browser. No timestamp or date is sent anywhere.
Tips
The “now” moment changes continuously, so when you convert a timestamp the corresponding time is tied to the moment of conversion. If you store timestamps in your database, be consistent about the unit — picking seconds everywhere avoids confusion later. The relative display is handy for quickly judging how old an event is.
When reading timestamps from APIs, check the format the API returns. HTTP dates and many JSON payloads use seconds, while JavaScript’s Date and several libraries use milliseconds. Auto-detection here removes the guesswork, but knowing your source helps you sanity-check the result.
Why use it
Timestamps appear constantly in logs, database records, API responses and code. Converting them by hand between Unix seconds and a human-readable date is tedious and prone to error. Doing it in the browser is instant, private and free — no install, no upload, just the answer in seconds.
Real-world use cases
- API development: Format JSON responses from Chrome DevTools before committing fixtures.
- Debugging: Validate timestamps, regex or hashes without switching to a terminal or IDE.
- On-call fixes: From your phone, quickly convert timezone or generate a UUID for a hotfix branch.
How it compares
| Tool | Offline | Privacy | Setup | Cost |
|---|---|---|---|---|
| This tool | Yes | 100% local | None | Free |
| Server tools | No | May log IP | None | Free/Ads |
| CLI / IDE plugin | Yes | Local | Install & config | Free |
For quick checks without context switching, the browser tool is fastest. For CI, keep the CLI as source of truth.
Pro tips
- Bookmark the tool. With prefetch enabled, it opens near-instantly next time.
- For secrets like hashes with salts, prefer your local terminal for production values.
- Pair UUID/Password generators with your password manager for rotation workflows.