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Paste a Unix timestamp and see it as ISO 8601, your local time, and a relative description ("3 days ago") — or pick a date and get the epoch value in seconds and milliseconds. The live current-timestamp readout at the top is there because half of all visits to a tool like this are someone needing "now" for a query or API call. Second vs millisecond inputs are detected automatically by digit count.
Frequently asked questions
Seconds or milliseconds — which does my timestamp use?
Count digits: ten digits (≈1.7 billion) is seconds — the Unix standard; thirteen digits is milliseconds — what JavaScript's Date.now() returns. Mixing them up puts dates in 1970 or the year 56,000, which is also how you spot the mistake.
Are Unix timestamps timezone-dependent?
No — that's their virtue. A timestamp counts seconds since 1 January 1970 UTC, identical everywhere on Earth. Timezones only appear when you format it for humans, which is why this tool shows UTC and your local time separately.
What is the year 2038 problem?
Systems storing timestamps as signed 32-bit integers overflow on 19 January 2038. Modern systems use 64 bits and are fine for 292 billion years; the problem lives on in old embedded systems and legacy databases.