Unix Timestamp Converter
Runs in your browser — your data is never uploaded.
Paste a Unix timestamp to see the human-readable date, or paste a date to get its epoch seconds and milliseconds. OkConverter auto-detects whether a number is in seconds or milliseconds by its magnitude — the classic gotcha when eyeballing logs — and shows ISO 8601, RFC 7231 and both epoch forms side by side. Entirely local, instant, and free.
0 characters · runs entirely in your browser
How to use Unix Timestamp Converter
- 1
Paste a Unix timestamp (e.g. 1721556000) or a date string (e.g. 2026-07-21T10:30:00Z).
- 2
Click “Convert” — numbers become dates, dates become timestamps.
- 3
Copy whichever representation you need: ISO 8601, RFC 7231, epoch seconds or milliseconds.
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Frequently asked questions
How does it know if my number is seconds or milliseconds?+
By magnitude: values of 1,000,000,000,000 (1e12) and above are treated as milliseconds, smaller values as seconds. Current dates are ~1.7 billion in seconds and ~1,700 billion in ms, so the two ranges don’t overlap for modern timestamps.
What date formats can I paste?+
Anything JavaScript’s date parser accepts — ISO 8601 (2026-07-21 or 2026-07-21T10:30:00Z) is the most reliable. A bare date like 2026-07-21 is interpreted as midnight UTC.
What is the Unix epoch?+
Midnight UTC on January 1, 1970 — the zero point from which Unix time counts seconds. It’s the near-universal machine representation of time in APIs, databases and logs.
Does it handle dates before 1970 or far in the future?+
Yes — negative timestamps (pre-1970) and anything within JavaScript’s ±100-million-day range (roughly ±273,000 years) convert fine.