Unix Timestamp Converter

Unix Timestamp Converter — Epoch Time to Human Date and Back

Every log file, database row, JWT expiry, and API response eventually confronts you with a number like 1751600000 and the question: when is that? This free converter translates Unix timestamps to human-readable dates and back, auto-detecting seconds vs milliseconds, showing UTC and your local time simultaneously, and outputting ISO 8601 for code. Instant, in-browser, no signup.

Timestamp Reference Points

Seconds vs Milliseconds: The #1 Timestamp Bug

A 10-digit number is seconds; a 13-digit number is milliseconds. Feed a millisecond value into a function expecting seconds and your date lands tens of thousands of years in the future; do the reverse and everything reads as January 1970. JavaScript's Date.now() returns milliseconds while most Unix tools and databases use seconds — this converter labels which it detected so the mismatch is caught before it ships.

Getting Timestamps in Every Environment

JavaScript:  Math.floor(Date.now() / 1000)
Python:      import time; int(time.time())
PHP:         time()
Java:        Instant.now().getEpochSecond()
Go:          time.Now().Unix()
MySQL:       SELECT UNIX_TIMESTAMP();
PostgreSQL:  SELECT EXTRACT(EPOCH FROM NOW())::int;
Linux/macOS: date +%s

Why Timestamps Beat Date Strings in Systems

Timestamps are time-zone-free, sort numerically, compare with simple integer math, and occupy 4–8 bytes. Date strings vary by locale, invite parsing ambiguity (is 04/07 April or July?), and break sorting. Best practice: store timestamps, display formatted dates — converting at the presentation layer, which is exactly the round-trip this tool lets you verify.

Free, Instant, Private

All conversion runs locally in your browser with no rate limits and nothing logged — handy as a permanent tab during any debugging session.