Unix timestamp
Converts Unix timestamp ↔ date (both directions). Seconds, milliseconds, local and UTC representation, weekday, relative time. Plus a reference of iconic timestamps.
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Timestamp ↔ date converter
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Famous Unix timestamps
click a row to load into the converter03
About the Unix epoch
Unix epoch
POSIX1970-01-01 00:00:00 UTC
The reference point — 1 January 1970, 00:00:00 UTC. A timestamp is the number of seconds since that moment. The format is timezone- and language-independent, which is why it was chosen as universal. It's used in all Unix-like systems, JavaScript, Python and virtually every API.
Seconds vs milliseconds
10 vs 131 741 434 000 = sec · ...000 = ms
The classic Unix timestamp is in seconds — a 10-digit number until year 2286. JavaScript uses milliseconds (Date.now()), 13 digits. Microseconds (16 digits) — in high-precision systems. Our converter detects the scale automatically by the length.
Y2K38 problem
2038-01-192 147 483 647 → int32 overflow
At 03:14:07 UTC on 19 January 2038 a 32-bit signed int will overflow, and systems storing timestamps in int32 will 'roll over' to 1901. Affects C, old Unix, embedded systems. Modern OSes and databases use 64-bit ints — enough for 292 billion years.
UTC — universal
Timezonestimestamp identical worldwide
The same timestamp in Moscow, Tokyo and New York denotes the same moment in time — only the local representation differs. That's why timestamps are ideal for logs and databases: no timezone juggling when comparing.