Unix Timestamp Converter
Unix Timestamp Converter turns a Unix timestamp into a readable date and turns a date back into a Unix timestamp, entirely in your browser.
Unix timestamp → Date
Auto: a value below 100,000,000,000 in size is read as seconds, otherwise as milliseconds.
Date → Unix timestamp
Your browser time zone is
Local times are converted with the browser's own time zone rules. An hour skipped at the spring change is shifted; an hour repeated at the autumn change resolves to one of the two instants.
Precision is one millisecond. Nanoseconds are not supported.
How to use it
- In the Timestamp → Date panel, paste a Unix timestamp and choose Seconds, Milliseconds, or Auto
- Select Convert to read the UTC time, your local time with its zone name, and the ISO 8601 string
- In the Date → Timestamp panel, enter a date and time and pick UTC or your local zone
- Select Convert, then copy the Unix seconds, Unix milliseconds, or ISO value; use Now to fill the current instant
Paste a timestamp and choose Seconds, Milliseconds, or Auto — Auto reads a value below 100,000,000,000 in size as seconds and anything larger as milliseconds, and you can always force the unit. It shows the instant as UTC (for example 2026-08-29 19:30:00 UTC), as your local time labelled with the browser time zone name such as Europe/Paris, and as an ISO 8601 / RFC 3339 string like 2026-08-29T19:30:00.000Z, plus the value normalised to both Unix seconds and Unix milliseconds. Going the other way, enter a date and time, pick UTC or your local zone, and read the Unix seconds, milliseconds, and ISO output. Timestamp 0 is 1970-01-01T00:00:00Z and negative timestamps point before 1970. Local conversions use the browser's own daylight-saving rules: a wall-clock time skipped at the spring change is shifted and flagged, and a time repeated at the autumn change resolves to one instant. Precision is one millisecond; nanoseconds are not supported, and values outside the range JavaScript dates can represent are rejected. This is a format converter, not a duration calculator: to measure the gap between two dates, use the Date Difference Calculator. Nothing you enter is uploaded.
FAQ
A Unix timestamp is a count of time since 1970-01-01 00:00:00 UTC, the Unix epoch. It is usually expressed in seconds and sometimes in milliseconds. Because it is anchored to UTC, the same timestamp names the same instant everywhere.
You choose. Seconds and Milliseconds force the unit; Auto reads a value whose size is below 100,000,000,000 as seconds and anything larger as milliseconds, which separates plausible second timestamps from millisecond timestamps after late 1973.
Yes. Zero is 1970-01-01T00:00:00Z, and negative values point to instants before 1970 — for example -86400 is 1969-12-31T00:00:00Z. Both directions of the converter accept them.
Local conversions use the browser's own time-zone rules. A wall-clock time that does not exist because clocks jumped forward is shifted to the next valid time and flagged; a time that occurs twice because clocks fell back resolves to one of the two instants. UTC conversions are never affected.
No. Every conversion uses the browser's built-in Date and Intl objects and runs on your device. Nothing you enter is uploaded to Tooliba or a third party, and analytics records only that the tool was used.