Convert Unix seconds, milliseconds, and date-time values with automatic precision detection plus local, UTC, ISO 8601, and relative output
Unix seconds
1789803344
Unix milliseconds
1789803344952
ISO 8601 / RFC 3339
2026-09-19T07:35:44.952Z
Conversion is local. Auto mode infers seconds, milliseconds, microseconds, or nanoseconds from digit count; choose an explicit unit for short values or unusual ranges. Date input uses the browser timezone and also returns standard UTC.
Convert Unix seconds, milliseconds, and date-time values with automatic precision detection plus local, UTC, ISO 8601, and relative output. It requires no desktop installation and supports common developer workflows directly in a modern browser.
Core processing runs locally in your browser. Tool input is not uploaded; downloads and clipboard actions are handled by the browser.
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