Unix Timestamp Converter
Timestamp to date
Enter a timestamp to see the date in UTC.
Date to timestamp
Enter a date to see its Unix timestamp.
Paste a Unix timestamp to see the exact date and time in UTC, or paste a date to get its Unix timestamp. The converter detects whether your number is in seconds or milliseconds, lets you force a unit when you need to, and shows clear results in ISO 8601 and readable UTC formats. Everything runs in your browser, so your data never leaves your machine.
How to use
- Type or paste a Unix timestamp into the timestamp field.
- Leave the unit on Auto, or pick Seconds or Milliseconds to force how the number is read.
- Read the UTC, ISO 8601, seconds, and milliseconds values in the results panel.
- To go the other way, enter a date (such as an ISO 8601 string) in the date field to get its timestamp.
- Use the copy buttons to grab a value, or Reset to clear both fields.
Examples
- Timestamp 1609459200 (seconds) converts to Fri, 01 Jan 2021 00:00:00 GMT.
- Timestamp 1609459200000 is read as milliseconds and gives the same moment, 2021-01-01T00:00:00.000Z.
- Date 2021-01-01T00:00:00Z converts to 1609459200 seconds.
FAQs
- What is a Unix timestamp?
- A Unix timestamp is the number of seconds that have passed since midnight UTC on 1 January 1970, known as the Unix epoch. It is a compact, time zone free way to represent a single moment in time.
- How does the converter tell seconds from milliseconds?
- On Auto, any value with an absolute magnitude of one trillion or more is treated as milliseconds, since a seconds value that large would land tens of thousands of years in the future. You can override this by choosing Seconds or Milliseconds from the unit menu.
- Why is the result shown in UTC?
- UTC is the reference time zone for Unix timestamps, so showing the date in UTC avoids confusion from local time zones and daylight saving changes. The ISO 8601 output ends in Z to make the UTC offset explicit.
- Can I convert timestamps from before 1970?
- Yes. Negative timestamps represent moments before the Unix epoch. For example, -1 in seconds is one second before 1970, which is 1969-12-31T23:59:59.000Z.
- What happens if I enter something that is not a number?
- The converter validates your input and shows a short error message instead of a broken result. Empty fields, fractional numbers, and non-numeric text are all caught.
- Does this tool send my data anywhere?
- No. All conversion happens locally in your browser. Nothing you type is uploaded or stored.
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