Does it auto-detect seconds vs milliseconds?

Yes. In auto mode, integers with 13 or more digits are treated as milliseconds and shorter values as seconds. You can also force a unit if needed.

What does relative time mean?

It is the gap between the timestamp and the current moment expressed in plain language, such as "2 hours ago" or "in 5 days", using your browser locale.

Is my timestamp sent anywhere?

No. All conversion happens locally in your browser using the built-in Intl.RelativeTimeFormat API — no network requests are made.

What is a Unix timestamp?

A Unix timestamp is the number of seconds (or milliseconds) elapsed since 00:00:00 UTC on 1 January 1970, known as the Unix epoch. It is the most common way computers store a point in time, independent of timezone.

How do I know if my value is in seconds or milliseconds?

A 10-digit value like 1700000000 is in seconds; a 13-digit value like 1700000000000 is in milliseconds. In auto-detect mode the tool treats anything from 10^12 up as milliseconds, and you can override it manually.

Does relative time use my timezone?

The relative phrase ("2 hours ago") is timezone-independent because it is just the gap from now. The exact date shown underneath is rendered in your browser's local timezone, with the ISO 8601 UTC string alongside it.

Why does my timestamp show a 1970 date?

A date near 1 January 1970 usually means the value is far smaller than expected — for example a duration in seconds rather than a real timestamp, or a millisecond value mistakenly read as seconds. Switch the unit or check the digit count.

Timestamp to Relative Time Converter

Timestamp to relative time

This tool turns a Unix timestamp — in seconds or milliseconds — into a human-readable phrase like “3 hours ago” or “in 2 days”. It is built for developers reading log lines, API responses or database created_at fields, where a raw epoch number tells you nothing at a glance. It also shows the exact local date and the ISO 8601 string so you can verify the conversion.

How it works

The input is parsed to milliseconds: in auto-detect mode, values of 10^12 or larger are treated as milliseconds and smaller values as seconds (you can force either unit). The tool then computes the gap between that moment and now and steps it up through divisions — seconds, minutes, hours, days, weeks, months, years — stopping at the first unit where the magnitude is below the next threshold. It uses the browser’s built-in Intl.RelativeTimeFormat so the phrasing matches your locale (“yesterday”, “last week”).

Example

The timestamp 1700000000 (seconds) is 14 November 2023, 22:13 UTC. Pasted today it reads as roughly “2 years ago”, with the exact local date and ISO string shown below.

Gap from now	Relative phrase
45 seconds ago	45 seconds ago
2 hours ago	2 hours ago
1 day ahead	tomorrow
3 weeks ahead	in 3 weeks
14 months ago	1 year ago

Everything runs in your browser; no timestamp leaves the page.