Convert between Unix timestamps and human-readable UTC/ISO dates.
Execution runs 100% locally inside the browser sandbox using HTML5 Canvas, Web Cryptography Subtle API, and Web Workers. Zero egress.
Zero network latency. Operates completely offline with zero dependencies on third-party backend servers or cloud services.
Built according to official RFC specifications, cryptographic test vectors, and enterprise-grade data transformation standards.
Input a Unix timestamp (seconds or milliseconds) or pick a calendar date.
View instant conversions in UTC, local timezone, ISO 8601, RFC 2822, and relative time.
Copy any date string format with one click for database and API queries.
A Unix timestamp is the total number of seconds elapsed since January 1, 1970 00:00:00 UTC.
10-digit numbers are automatically treated as seconds and 13-digit numbers as milliseconds.
Zero-egress companion tools in the Date & Time suite
Convert Microsoft Excel 1900 date system serial integers into standard ISO 8601 timestamps.
Calculate continuous Julian Day Numbers (JDN) and Modified Julian Date (MJD) from Gregorian dates.
Convert high-precision 19-digit nanosecond timestamps into formatted UTC strings.
Check exact clock shift dates and hour offsets for US, EU, and global timezones.
