Unix Timestamp Converter
Convert Unix timestamps to dates and back. Auto-detects seconds vs milliseconds, shows ISO, UTC and local formats plus relative time. Runs entirely in your browser.
Runs locally · data never uploaded
Advertisement
How to use
What it does
A Unix timestamp counts the seconds (or milliseconds) elapsed since 1970-01-01 00:00:00 UTC. This tool auto-detects whether your input is seconds or milliseconds: 10 digits are treated as seconds, 13 as milliseconds.
Example
Input 1700000000 (seconds) gives:
2023-11-14 22:13:20 UTC
2023-11-15 06:13:20 localInput 2023-11-15 06:13:20 converts back to 1700000000.
About time zones
Results include ISO 8601 (UTC), a UTC rendering, and a local rendering formatted for your locale. If your result is off by 8 hours, you probably mixed up seconds and milliseconds.
FAQ
Q1.Why is my result off by 8 hours?
Almost always a time zone difference. A Unix timestamp carries no zone; it is rendered using your browser zone. Users in UTC+8 see local time shifted accordingly — check the row labelled UTC if you want the raw value.
Q2.What's the difference between 10-digit and 13-digit timestamps?
10 digits are seconds (e.g. 1700000000); 13 digits are milliseconds (e.g. 1700000000000). This tool detects it automatically, or you can pick the unit explicitly.
Q3.What is the Year 2038 problem?
A signed 32-bit integer maxes out at 2147483647, which is 2038-01-19 03:14:07 UTC. JavaScript uses double-precision floats and is unaffected, but backends storing timestamps in 32-bit ints need care.
Advertisement
Related tools
Time Zone Converter & Date CalcConvert a moment across time zones and compute date differenNumber Base Converter (2/8/10/16/36/62)Convert between binary, octal, decimal, hexadecimal, 36 and JSON Formatter & MinifierFormat, beautify and minify JSON online. Custom indent, sortUUID & ULID GeneratorGenerate UUID v4, v7 and v1 plus ULID online. Batch generate