Unix Timestamp Converter

Convert Unix timestamps to human-readable dates and back. Supports seconds and milliseconds, with relative time display.

Current Unix Timestamp

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Timestamp to Date

Unix Timestamp

Date to Timestamp

Date & Time

Features

Timestamp → date formats

Date → timestamp

Seconds & milliseconds

Relative time display

Live current timestamp

How to Use

1. Type a Unix timestamp into the timestamp field — the date updates live.

2. Or pick a date and time — the timestamp updates live.

3. The current timestamp is shown live at the top.

About this tool

A Unix timestamp counts seconds since 00:00:00 UTC on 1 January 1970, which is how databases, APIs and log files store moments in time without worrying about time zones. This converter turns a timestamp into readable dates — ISO 8601, UTC, your local time and a relative description like "3 hours ago" — and turns a date and time back into a timestamp in both seconds and milliseconds. It detects milliseconds automatically: values of 13 digits, as produced by JavaScript's Date.now(), are treated as milliseconds. The current timestamp ticks live at the top so you can copy "now" in one click. It is handy for debugging API responses, reading log lines, and checking token expiry times.

Frequently Asked Questions

What is the difference between seconds and milliseconds timestamps?

Unix time is traditionally counted in seconds (10 digits for current dates), used by most databases and languages. JavaScript and Java often use milliseconds (13 digits). The converter treats values of 1,000,000,000,000 and above as milliseconds.

Do Unix timestamps depend on time zone?

No. A timestamp represents the same instant everywhere. Time zones only matter when the instant is displayed as a local date and time, which is why the tool shows both UTC and your local time.

What is ISO 8601?

It is the international date format YYYY-MM-DDTHH:MM:SSZ, for example 2026-09-11T08:30:00Z. The Z means UTC. It sorts correctly as text and is the safest format for APIs and data exchange.

What is the Year 2038 problem?

Systems that store Unix time as a signed 32-bit integer overflow on 19 January 2038 at 03:14:07 UTC. Modern systems use 64-bit timestamps, which will not overflow for billions of years.

How are leap seconds handled?

Unix time ignores leap seconds: every day is treated as exactly 86,400 seconds. In practice this means timestamps and UTC can differ by the leap seconds added since 1972, which almost never matters for applications.