ToolFoxUnix Timestamp Converter
Convert Unix timestamps to human dates and back — auto-detects seconds vs milliseconds.
- Detected unit
- seconds
- ISO (UTC)
- 1970-01-01T00:00:00.000Z
- Local time
- 1/1/1970, 12:00:00 AM
How it works
A Unix timestamp counts time from 1 January 1970 UTC. Values around 10 digits are interpreted as seconds and 13 digits as milliseconds (the tool auto-detects at the 1e12 boundary), then shown as ISO-8601 UTC and your local time. The reverse direction converts any date-time you pick into both units.
Example
1700000000 is 2023-11-14T22:13:20Z — the same instant as 1700000000000 in milliseconds. API logs usually use one or the other; the detected unit is shown so you always know which you pasted.
Frequently asked questions
Why is my date off by hours?
Timestamps are UTC; the local-time line applies your device's timezone. Both are shown to avoid confusion.
What is the year-2038 problem?
Signed 32-bit second counters overflow on 19 January 2038; modern 64-bit systems (and this tool) are unaffected.
Does it handle negative timestamps?
Yes — negative values represent dates before 1970.
Seconds or milliseconds — which should I use?
JavaScript uses milliseconds, most Unix tools and APIs use seconds. The converter shows both.
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