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🔄 Timestamp Converter
Unix timestamps (seconds since 1970-01-01 UTC) are everywhere in APIs and logs. This converter goes between Unix seconds, Unix milliseconds, ISO 8601 strings, and your local timezone — so you can read what your server logs are telling you.
Examples
17356896002025-01-01 00:00:00 UTC17356896000002025-01-01T00:00:00.000Z2026-12-31T23:59:59Z1798761599Frequently asked questions
Seconds or milliseconds — how do I tell?
A Unix timestamp in seconds is currently 10 digits (around 1.7 billion). In milliseconds it is 13 digits. JavaScript Date uses milliseconds; most other languages use seconds.
What is the epoch?
January 1, 1970 00:00:00 UTC. Unix timestamps count seconds (or ms) elapsed since then. Negative numbers represent dates before the epoch.
Will Unix timestamps overflow?
A 32-bit signed Unix timestamp overflows in January 2038 — the Y2K38 problem. 64-bit integers (used everywhere modern) push the overflow billions of years out.
Is the Unix timestamp affected by timezones?
No. Unix timestamps are always UTC by definition. The conversion to local time happens in the display layer.
What about leap seconds?
Unix time ignores them — every UTC day is exactly 86,400 seconds. Real wall-clock time can drift slightly during leap second events, but this rarely matters for app code.
About this tool
Timestamp Converter runs entirely in your browser using standard Web APIs. No data is sent to any server. The source for this tool is in our public GitHub repository.
Related tools
- 🌐 Time Zone Converter — Convert any time to major world time zones (US, EU, Asia).
- 📅 Date Difference — How many days, weeks, months between two dates? Plus workdays.
- 📅 Working Days Calculator — Count business days between two dates, excluding weekends and optional holidays.
Why this tool
vs typical free web-tool sites
| 1vw | Typical free site | |
|---|---|---|
| Price | Free | Free |
| Signup required | No | Often (for premium features) |
| Ads inside the tool | No | Yes (banner + video) |
| Data sent to server | No (browser-only) | Yes (inputs analyzed for ads) |
| Total tools | 96 | Often <20 or scattered across sites |
| Bookmarkable URL per tool | Yes | Mixed |
| Loads in under 1s | Yes (static) | Often slow (ad tracking) |
| Multilingual | EN / ES / PT / FR / DE | Usually EN only |
| Open source | Yes | No |