What a Unix Timestamp Is
A Unix timestamp counts the seconds elapsed since January 1, 1970, 00:00:00 UTC — the "epoch". It's the standard way databases, APIs and log files store points in time, because a single integer is unambiguous: no time zones, no date formats, no daylight-saving confusion.
Worked example: 1750000000 converts to Sun, 15 Jun 2025 15:06:40 UTC. The tool shows that alongside your local time, the ISO 8601 form (2025-06-15T15:06:40.000Z), and a relative label like "3 weeks ago" — one input, four readable answers, plus a copy-all button.
Both Directions
Switch modes to go the other way: paste any date string a browser can parse — 2026-05-02T12:00:00, May 2, 2026 — and get the Unix timestamp in seconds, in milliseconds, and the normalized ISO string. The "Use Current Timestamp" button fills in the epoch time for right now, handy for quick sanity checks against log entries.
Seconds vs. Milliseconds — the #1 Pitfall
Unix time comes in two common resolutions, and mixing them up produces absurd dates:
| Digits | Unit | Used by | Example |
|---|---|---|---|
| 10 | Seconds | Unix tools, PHP, Python, most APIs | 1750000000 |
| 13 | Milliseconds | JavaScript Date.now(), Java | 1750000000000 |
This converter expects seconds. Paste a 13-digit millisecond value and you'll land tens of thousands of years in the future — if the result looks like the year 57432, drop the last three digits and try again. Converting a date to a timestamp gives you both units, so you can pick whichever your code needs.
Time Zones and Other Gotchas
- Timestamps have no time zone.
1750000000is the same instant everywhere; only its display differs. The tool shows both UTC and your local zone so you can see the offset at a glance. - Date strings without a zone are ambiguous.
2026-05-02T12:00:00is interpreted in your local time zone; appendZto pin it to UTC. - The year-2038 problem: signed 32-bit systems overflow at timestamp 2,147,483,647 (Jan 19, 2038). Modern 64-bit systems — and this tool — are unaffected.
All conversion happens in your browser; nothing is sent to a server. Working with API payloads? Pretty-print them first in the JSON formatter, or generate request IDs with the UUID generator.