Unix Timestamp Converter

Convert Unix seconds or milliseconds to readable dates and back. Free browser-based tool with no signup required.

About Unix Timestamp Converter

Convert Unix seconds or milliseconds to readable dates and back.

The tool is designed to process data in the browser unless the interface explicitly states that a network request is required.

How to use this tool

Enter or select the timestamp, epoch, date value you want to work with.
Review the available settings, then run the convert action.
Review the timestamp, date, unix time output and use the copy or download action when the tool provides one.

What you can do with Unix Timestamp Converter

Convert epoch to date
Turn date into unix timestamp

What this conversion does

Convert a Unix timestamp in seconds or milliseconds to a readable date (local, ISO 8601, or UTC), or turn any date string into Unix seconds and milliseconds.

Example input

1735689600 (unit: auto, output: ISO 8601)

Example output

2025-01-01T00:00:00.000Z — plus the same instant in your local time

Practical workflow

Pick Timestamp to Date or Date to Timestamp.
Paste the value. Auto treats absolute values below 10,000,000,000 as seconds and larger values as milliseconds; explicitly choose Seconds or Milliseconds for ambiguous values.
Choose the primary output — local time, ISO 8601, or UTC — and copy either result card.
Use Now to insert the current time, or Use result as input to flip direction and continue converting.

Common use cases

Read a created_at or expires_at value from an API response or database row.
Turn a log entry's epoch millisecond value into a human-readable moment while debugging.
Generate the exact Unix seconds for a scheduled job, a JWT exp claim, or a cache expiry.

Important notes and limitations

Conversion runs entirely in your browser and the live “current Unix time” ticker updates every second.
Local output uses your browser's time zone and locale. For a specific zone, take the ISO value to the Time Zone Converter.
Millisecond precision is preserved: 1735689600000 converts to the same instant as 1735689600, and Date to Timestamp always shows both seconds and milliseconds.
Input and settings are remembered in browser local storage. Only seconds and milliseconds are supported; convert microseconds or nanoseconds before entering them.

Continue your workflow

Time Zone Converter — view the converted instant in any IANA time zone.
Cron Expression Parser — check when a schedule will actually run.

Frequently asked questions

How do I tell whether a timestamp is in seconds or milliseconds?

Typical current timestamps use ten digits for seconds and thirteen for milliseconds. Auto applies a magnitude heuristic; select the unit explicitly for near-epoch millisecond values or distant future timestamps.

What is the difference between ISO 8601 and UTC output?

Both describe the same instant in UTC. ISO 8601 is the machine-friendly 2025-01-01T00:00:00.000Z form used in APIs and JSON; the UTC option prints the RFC 1123 style used in HTTP headers.

Why does the local date differ from the ISO date?

Your browser's time zone offset is applied to the local view. Around midnight the calendar date can therefore differ from the UTC date shown in the ISO string.

Can I convert a date string like 2025-01-01 to a timestamp?

Yes. Switch to Date to Timestamp and paste any date the browser can parse, including ISO strings with a time and offset. A date with no time is treated as midnight UTC.

Focused guides for this tool

Unix Timestamp to Date Converter — Translate Unix epoch timestamps into human-readable UTC, ISO 8601, and local dates.
Timestamp to Date Converter — Inspect a numeric timestamp as ISO 8601, UTC text, or a date in your browser's local time zone.
Epoch to Date Converter — Translate numeric epoch values into standard human calendar dates.