Instacode

Unix Timestamp Converter

Convert Unix timestamps in seconds or milliseconds to local and UTC dates, convert dates back, and watch the current timestamp tick.

Unix Timestamp Converter · saved on this device only

This unix timestamp converter is for developers, analysts and anyone reading logs, databases or API responses full of numbers like 1700000000. Paste a timestamp and it shows the date in UTC and in your local time zone, along with ISO 8601, RFC 2822 and a relative time. It reads seconds, milliseconds, microseconds and nanoseconds.

You can also type a date to get its timestamp, or paste a whole list and export the results as CSV. A live clock at the top shows the current Unix time. Everything is calculated in your browser and nothing is uploaded. Your last inputs are kept only in this browser's local storage, and “Reset” clears them.

How to use it

  1. Check the live clock at the top. Use “Pause” to freeze it, or “Convert this” to send the current seconds to the converter.
  2. In the “Timestamp → Date” tab, paste a number into “Unix timestamp”. Leave Unit on “Auto” or pick s, ms, µs or ns yourself.
  3. Read the UTC and Local rows, and optionally choose a zone under “Also show in time zone”. Press “Copy” on any row to copy that value.
  4. Switch to “Date → Timestamp”, type a date such as 2024-03-15 14:30:00 or use the calendar picker. Choose “Local” or “UTC” for dates that have no zone.
  5. For a list, open “Batch”, paste one timestamp or date per line, then use “Copy CSV” or “Download CSV”.
  6. Press “Reset” in the header to clear everything and start over.

What it does

  • A live “Current Unix time” clock showing seconds, milliseconds, UTC and local time, with “Pause”, “Copy seconds”, “Copy milliseconds” and “Copy ISO” buttons.
  • Unit auto-detection for seconds, milliseconds, microseconds and nanoseconds, with a manual override.
  • Timestamp results in UTC and local time, ISO 8601, RFC 2822, relative time, seconds and milliseconds, each with its own “Copy” button.
  • An optional extra time zone picked from the list your browser supports.
  • Date to timestamp conversion that accepts formats like 2024-03-15, 2024-03-15T14:30:00+02:00 and “March 15, 2024 2:30 PM”, plus a calendar picker.
  • A “Batch” mode that converts up to 1000 lines at once and exports them with “Copy CSV” or “Download CSV”.
  • A note when a timestamp is past 2147483647, the limit of a signed 32-bit value.

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Convert Unix timestamps (seconds and milliseconds) to dates in local and UTC and back, with the current timestamp ticking live.

Questions

Is this unix timestamp converter free?

Yes. It is free, needs no sign-up, and works offline once the page has loaded.

Is my data uploaded or stored anywhere?

No. All conversions run in your browser. Your last inputs are saved only in this browser's local storage so they are there when you return, and “Reset” clears them.

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

Roughly 10 digits means seconds and 13 digits means milliseconds. In “Auto” mode the tool guesses from the size of the number, and you can pick s, ms, µs or ns yourself if the guess is wrong.

How do I save or export the results?

Each result row has a “Copy” button. In the “Batch” tab you can use “Copy CSV” or “Download CSV”, which saves a file named timestamps.csv.

What is the year 2038 problem?

A signed 32-bit integer tops out at 2147483647, which is 2038-01-19 03:14:07 UTC. Systems that still store timestamps in 32 bits will overflow after that point.

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Updated October 12, 2026