Unix Timestamp Converter

Runs in browser Utilities

Focused on Unix time: shows the live current epoch, converts seconds to date and date to seconds, and lists the 32-bit overflow date (2038) and other useful reference points.

Privacy: This tool runs entirely in your browser. Your input never leaves your device.

What is an ISO 8601 timestamp, and how does it relate to Unix time?

ISO 8601 writes a moment as 2026-09-23T10:15:00+03:00 — largest unit first, with an explicit UTC offset or Z — so it sorts as text and is unambiguous across locales; RFC 3339 is the Internet profile APIs use. Unix time is the same moment as a count of seconds (or milliseconds in JavaScript) since 1970-01-01T00:00:00Z, with no time zone at all. Most date bugs are an offset applied twice or a local time stored as if it were UTC.

How to use Unix Timestamp Converter

  1. Enter Unix seconds (for example 1700000000) or a date.
  2. Pick the timezone for the readable output.
  3. Click "Use current time" to convert the present moment.

Unix Timestamp Converter features

  • Live current Unix time in seconds and milliseconds
  • Seconds → date and date → seconds in one field
  • Local and UTC renderings with RFC 2822 and relative time
  • Reference table with the 1970 epoch, 10^9 milestones and the 2038 overflow
  • Warnings for values beyond the 32-bit range and negative timestamps

Unix Timestamp Converter example

Read a log timestamp

Input:

1700000000

Output:

Tue, 14 Nov 2023 22:13:20 +0000 (UTC)
ISO 8601 (UTC): 2023-11-14T22:13:20.000Z

Frequently asked questions about Unix Timestamp Converter

What is Unix time?

The number of seconds elapsed since 00:00:00 UTC on 1 January 1970, not counting leap seconds. It is the same everywhere in the world; only its rendering as a date depends on the timezone.

What is the year 2038 problem?

Systems that store Unix time in a signed 32-bit integer overflow at 2,147,483,647 seconds — 19 January 2038 03:14:07 UTC. The tool flags any value beyond that limit.

Can I enter a date to get its timestamp?

Yes — type an ISO or RFC 2822 date (or "now") and the tool returns epoch seconds and milliseconds.

How do I get the current Unix time?

It is displayed at the top of the results on every run; click "Use current time" to convert the present moment.

Technical notes

Numeric input is always read as epoch seconds: the engine's magnitude-based unit detection (detectTimestamp) is deliberately not used, so a millisecond value such as 1700000000000 becomes a date in the year 55840 rather than being reinterpreted. Values beyond ±8.64e12 seconds, the ECMAScript Date limit of ±275,760 years, are rejected. Fractions are kept (1700000000.75 → 750 ms) and 'Unix seconds' is floored, so −1.5 reports −2.

Date strings go through the ISO 8601 parser first, which accepts calendar, week (2024-W11-5), ordinal (2024-075) and basic (20240315T103000Z) forms, a comma decimal mark, 24:00:00 and the leap second 23:59:60 (clamped to :59); fractions round to the nearest millisecond. Strings without an offset are resolved in the selected zone via Intl.DateTimeFormat, spring-forward gaps moving forward. RFC 2822 is tried next (±hhmm and US abbreviations only), then the browser's Date.parse in the host zone.

References