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Timestamp Converter

Convert Unix timestamps to readable dates, or dates back to seconds and milliseconds.

Milliseconds
1789992109000
Seconds
1789992109
ISO
2026-09-21T12:01:49.000Z
Local
9/21/2026, 12:01:49 PM
UTC
Mon, 21 Sep 2026 12:01:49 GMT

Other useful tools

Free tools that often go together. Everything runs in your browser.

  • Developer toolsJSON FormatterFormat and validate JSON
  • Developer toolsBase64Encode and decode Base64
  • Developer toolsDiff TextCompare text lines
  • Developer toolsCSV to JSONConvert CSV and JSON both ways
  • Developer toolsHash GeneratorSHA-256 and other hashes
  • Developer toolsURL EncodeEncode and decode URLs

How to use this tool

  1. Choose epoch, date, or now.
  2. Enter a timestamp or date string when needed.
  3. Read the seconds, milliseconds, ISO, local, and UTC outputs.

Frequently asked questions

What is a Unix timestamp?▾

A Unix timestamp is the number of seconds that have passed since 1 January 1970 at midnight UTC, a fixed reference point called the Unix epoch. Computers often store dates this way internally because a single number is easier to compare, sort, and do math with than a formatted date string. Some systems use milliseconds instead of seconds for extra precision, which is why timestamps can look very different in length depending on where they came from.

Who uses this?▾

Developers reading log files or API responses that store dates as raw numbers, support staff investigating when an event happened from a database record, and anyone turning a timestamp from a webhook, spreadsheet, or bug report into a readable date.

How are seconds and milliseconds detected?▾

Numbers below 10,000,000,000 are treated as seconds. Larger numbers are treated as milliseconds, since a millisecond count for a modern date is a much bigger number.

Does this use my local timezone?▾

Local output uses your browser's timezone setting. The ISO and UTC outputs are timezone-neutral, so they stay the same no matter where you're located.

Why does my date shift?▾

Date strings without timezone information can be interpreted by your browser as local time instead of UTC, which shifts the resulting timestamp by your UTC offset. Include an explicit timezone in the input to avoid this.

Is anything uploaded?▾

No. Date conversion runs locally in your browser.

What outputs does the tool show?▾

For any timestamp or date you enter, it displays seconds, milliseconds, ISO, local time, and UTC side by side, so you can copy whichever format the system you're working with expects.

Processed locally in your browser. Your files are never uploaded to our servers.