What is a Unix timestamp?

A Unix timestamp is the number of seconds (or milliseconds) elapsed since 1 January 1970 00:00:00 UTC (the Unix epoch). It is a standard way to represent dates in programming.

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

A 10-digit number is typically seconds (valid up to year 2286). A 13-digit number is milliseconds. The tool auto-detects which format you have entered.

Is my data sent to a server?

All conversions run in your browser. No data is sent to our servers.

Can I get the current timestamp?

Yes. Click "Now" to insert the current Unix timestamp, useful for generating test values or setting expiry times.

Unix timestamp converter

Unix timestamp converter is a time tool that translates between Unix epoch timestamps and human-readable dates. It auto-detects seconds versus milliseconds, displays UTC, local, and relative time, and provides a live current-timestamp button. The tool runs in your browser.

Enter a value above to convert

MODE

Runs entirely in your browser

Dedicated pages

Direct links for each conversion mode.

Unix timestamp to date

Convert a Unix timestamp (seconds since epoch) to a human-readable date and time. Shows UTC, local time, and relative time.

Date to Unix timestamp

Convert any date and time to a Unix timestamp. Shows the result in both seconds and milliseconds.

Current Unix timestamp

See the current Unix timestamp updating live every second. Copy the timestamp in seconds or milliseconds.

Millisecond timestamp to date

Convert a Unix timestamp in milliseconds to a human-readable date. Used by JavaScript's Date.now() and many APIs.

How to convert a Unix timestamp

Paste a Unix timestamp (seconds or milliseconds) into the input field.
The tool converts it to a human-readable date and time instantly.
Toggle between UTC and your local time zone.
Or enter a date and time to get the corresponding Unix timestamp.

Common uses

Debugging API responses that contain Unix timestamps, use JWT decoder to inspect the exp and iat claims in auth tokens
Converting timestamps in server logs to readable dates
Getting the Unix timestamp for a specific date to use in a query or script. The date calculator is useful for adding or subtracting days from a date

Technical specification

Algorithm or formula: Constructs a JavaScript Date from the timestamp via new Date(value) (milliseconds) or new Date(value * 1000) (seconds). Reverse direction uses date.getTime() divided by 1000 for seconds output.
Browser API or library: Native Date and Intl.DateTimeFormat for locale-aware formatting; no external library.
Input limits: 10-digit values are treated as seconds (valid through year 2286), 13-digit values as milliseconds. Range follows ECMAScript Date limits (±100,000,000 days from 1970-01-01).
Output: UTC ISO string, local time formatted for your zone, and a human-readable relative time (e.g., "3 days ago"). Bidirectional: date-to-timestamp also supported.
Known limitations: Leap seconds are not represented (matches JavaScript Date semantics). Sub-second precision beyond milliseconds is not modeled.

Frequently asked questions

What is a Unix timestamp?: A Unix timestamp is the number of seconds (or milliseconds) elapsed since 1 January 1970 00:00:00 UTC (the Unix epoch). It is a standard way to represent dates in programming.
How do I know if my timestamp is in seconds or milliseconds?: A 10-digit number is typically seconds (valid up to year 2286). A 13-digit number is milliseconds. The tool auto-detects which format you have entered.
Is my data sent to a server?: All conversions run in your browser. No data is sent to our servers.
Can I get the current timestamp?: Yes. Click "Now" to insert the current Unix timestamp, useful for generating test values or setting expiry times.

Reviewed and tested May 25, 2026.