Unix Timestamp Converter Online — Epoch ↔ Date

Live Unix time, bidirectional epoch ↔ date convert (including local datetime), and a copy-ready format matrix (ISO, RFC 2822, SQL, relative). UTC or browser local — all in your browser, no upload.

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Unix timestamp converter — developer notes
Live clock, bidirectional epoch ↔ date sync, and a copy-first format matrix — all in the browser. Auto unit detection avoids confusing 10-digit seconds with 13-digit milliseconds.

How conversion works

After load, empty fields follow the live clock in the format matrix. Type an epoch, ISO date, or local datetime and the other fields update live (no Convert click required). Formats include epoch s/ms, ISO 8601, RFC 2822 (English tokens), SQL-like datetime, locale string, and relative time. Clear returns to live-now. Precision beyond milliseconds (e.g. 16+ digit under auto) is rejected — JavaScript Date is ms-only.

Options

Unit (auto / seconds / milliseconds)
Auto treats roughly 10-digit values as seconds and 11–15 digits as milliseconds; 16+ digits under auto are rejected as too precise. Force milliseconds to reinterpret a 10-digit value as ms.
Timezone (UTC / local)
Controls ISO, RFC, SQL, and locale rows. The Local date/time picker always uses your browser wall clock — even when display is UTC.

Examples

Epoch seconds → ISO (UTC)

Input

1710000000

Output

2024-03-09T16:00:00.000Z

ISO date → epoch

Input

2024-03-09T16:00:00.000Z

Output

1710000000 (seconds) / 1710000000000 (ms)

Related utilities

Need identifiers for fixtures? Use the UUID generator. Scheduling jobs? Check next runs with the cron parser. Number bases? Try the number base converter.

Unix timestamp FAQ

Epoch conversion questions

How does auto unit detection work?

About 10 absolute digits → seconds; 11–15 → milliseconds. Sixteen or more digits under Auto are rejected (too precise for Date). Force Milliseconds to treat a 10-digit value as ms instead of seconds.

Is my data uploaded?

No. Conversion runs entirely in your browser.

Do I need to click Convert?

No. Epoch, ISO text, and local datetime stay in sync as you type (light debounce). Clear restores the live-now matrix.

UTC vs local — and what about Local date/time?

Prefer UTC for logs and APIs. Display timezone switches the format matrix. The Local date/time control always edits browser wall clock for that Instant — it is never labeled as UTC.

Can I convert microseconds or nanoseconds?

No. JavaScript Date is millisecond precision; values that look like µs/ns under Auto are rejected rather than silently truncated.

Developer utilities

Timestamps, UUID, ULID, Nanoid, cron, passwords, regex, slugify, number bases, case, text diff, and chmod — all client-side.

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