Does it handle dates before 1970?

Yes. Negative timestamps represent dates before the Unix epoch.

What timezone is used?

Your local timezone by default, with UTC and arbitrary offset modes available.

Unix Timestamp Converter

Switch between Unix timestamps (seconds or milliseconds) and ISO-8601 dates. Shows the current timestamp and relative time, with timezone support.

Runs locally in your browser

Timestamp or date

Number unit

Thursday, April 30, 2026

10:10:00 AM · 0 seconds ago

Unix seconds1777543800

Unix millis1777543800000

ISO 8601 UTC2026-04-30T10:10:00.000Z

ISO local2026-04-30T10:10:00

RFC 2822Thu, 30 Apr 2026 10:10:00 GMT

Locale4/30/2026, 10:10:00 AM

Day of year120

Week of year18

WeekdayThursday

Now (sec)

1777543800

Now (ms)

1777543800388

Now (ISO)

2026-04-30T10:10:00.388Z

Timezone

UTC

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About Unix Timestamp Converter

Switch between Unix timestamps (seconds or milliseconds) and ISO-8601 dates. Shows the current timestamp and relative time, with timezone support.

Unix Timestamp Converter is part of FizzKit — a collection of focused, browser-based tools. Because everything runs locally, it works offline once loaded and never exposes your data to a remote server.

Frequently asked questions

The tool auto-detects based on magnitude — 10 digits are seconds, 13 are milliseconds. You can also force a mode.

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