File & Format Converters · Free tool
Timestamp Converter
Convert between Unix timestamps and ISO 8601 dates. Auto-detects ms vs seconds.
Updated May 2026
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What it does
Convert between Unix timestamps (seconds or milliseconds) and ISO 8601 / human-readable dates. Auto-detects ms vs seconds based on length.
Embed this tool on your siteShow snippetHide
Paste this snippet into any page. Loads on-demand (lazy), no tracking scripts, and sized to most dashboards. Replace the height to fit your layout.
<iframe src="https://freetoolarena.com/embed/timestamp-converter" width="100%" height="720" frameborder="0" loading="lazy" title="Timestamp Converter" style="border:1px solid #e2e8f0;border-radius:12px;max-width:720px;"></iframe>How to use it
- See the current Unix timestamp at the top.
- Type into either Unix or ISO field — the other updates.
- Use the 'Copy to fields below' button for now().
Frequently asked questions
- How is ms vs seconds detected?
- By length. 10 digits = seconds (e.g. 1717545600 = 2024-06-04). 13 digits = ms. The split point isn't perfect for far-future timestamps, but works for any plausible date.
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