Timestamp Converter
What is a UNIX timestamp?
A UNIX timestamp is the number of seconds since 1970-01-01 00:00:00 UTC (the Unix epoch). It’s widely used in APIs, logs, databases, and event systems.
Some systems use milliseconds instead of seconds. This tool detects common formats and helps you convert UNIX timestamps to ISO 8601 dates and back — locally in your browser.
How to use the Timestamp Converter
- Paste a UNIX timestamp into the first field (seconds or milliseconds).
- Click “→ ISO” to convert it to an ISO 8601 date (UTC).
- Paste an ISO date into the second field.
- Click “→ UNIX” to convert it back to a UNIX timestamp.
Tips and common pitfalls
- 10 digits usually means seconds; 13 digits usually means milliseconds.
- ISO strings ending with “Z” are in UTC; offsets like +02:00 mean local time zones.
- If your time looks wrong by hours, it’s usually a timezone/offset issue.
- Some systems store timestamps as strings; make sure there are no spaces or commas.
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Timestamp checks before storing or comparing a date
Confirm units, timezone, and precision because the same number can represent different moments when systems make different assumptions.
Seconds or milliseconds
Identify whether the value uses seconds, milliseconds, microseconds, or nanoseconds since the epoch before converting it.
UTC and local time
Store machine timestamps in UTC and apply a named timezone only for display or rules that depend on local civil time.
DST and ambiguity
Test daylight-saving transitions, nonexistent local times, repeated hours, and historical timezone changes.
Precision and range
Check rounding, fractional seconds, negative timestamps, platform range limits, and serialization between languages.
Privacy and usage
Built for quick checks without an account
Toolinix tools are designed for short developer tasks: paste a safe sample, inspect the result, copy what you need, and move on.
No login required
You can use the tools without creating an account, subscribing to a newsletter, or saving a workspace.
Local when possible
Formatters, generators, encoders, and text utilities generally run in your browser. Network diagnostics may need a server-assisted lookup to check public URLs, domains, or IPs.
Keep secrets out
Do not paste production passwords, private keys, access tokens, customer records, or regulated data into online tools unless your own security policy allows it.
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