Unix Timestamp to Date Converter
Convert a Unix timestamp to a human-readable date. Auto-detects seconds vs milliseconds, shows local, UTC, and ISO 8601 formats.
Timestamp → Date
About Unix to Date
This converter takes a Unix timestamp (seconds or milliseconds since 1970-01-01 UTC) and renders it as a human-readable date in three formats simultaneously: local time (honouring your browser's timezone), UTC, and ISO 8601. The auto-detection logic looks at the number's magnitude — values around 10 digits are treated as seconds, 13 digits as milliseconds — so you can paste what you have and trust the output. Use this direction when: a backend log line or database column gave you a bare integer and you need to know when it happened; you're debugging a JWT "exp" or "iat" claim (JWT uses seconds); you're sanity-checking a Stripe event timestamp (Stripe uses seconds in most places but milliseconds in a few newer fields — the converter handles both); you're reading event data from Unix-native tooling like `ls -l --time-style=+%s`. The ISO 8601 output ends with "Z" when the date is in UTC, or with an offset like "+02:00" for local time in non-UTC zones. Most API specifications (RFC 3339 subset of ISO 8601) require the "Z" or explicit offset; "2026-04-23T10:00:00" without a zone is ambiguous and should be avoided in new interfaces. Copy whichever format matches your target API's expectations.
Features
- Convert Unix timestamps to human-readable dates
- Convert dates to Unix timestamp format
- Support for multiple date formats and timezones
- View the current timestamp in real-time
How to Use
- Enter a Unix timestamp or select a date
- View the converted result in the other format
- Choose your preferred date format and timezone
- Copy the converted value to clipboard
Frequently Asked Questions
How does the converter know if my timestamp is seconds or milliseconds?
It looks at the magnitude. A 10-digit number (like 1735689600) is too small to be a reasonable millisecond timestamp — it'd place the date in 1970. 13-digit numbers are treated as ms. The threshold is around 9,999,999,999. You can override by multiplying or dividing by 1000 before pasting.
What timezone does the "local" output use?
Your browser's configured timezone — typically derived from the operating system. If you need a specific zone (e.g., "what is this timestamp in Tokyo"), use the ISO output as input to a dedicated timezone tool. The "UTC" output is always stable regardless of your location.
Why is the date I converted one day off?
Usually a timezone confusion. A timestamp like 1735603200 is Dec 31 midnight UTC — which is Dec 30 evening in the Americas and Jan 1 morning in Asia. The local output reflects your zone; to reason about the "day" unambiguously, use UTC.
Can I convert timestamps in nanoseconds?
Not directly — the converter expects seconds or milliseconds. For nanoseconds (common in Go's time.Now().UnixNano() or Prometheus metrics), divide by 1,000,000 first to get ms, then paste. You lose sub-millisecond precision but gain readable dates.
Other Timestamp Converter variants
Date to Unix
Convert a date/time into a Unix timestamp. Supports ISO 8601, RFC 2822, and browser datetime-local input. Returns seconds and milliseconds.
Millisecond Timestamp
Convert between Unix millisecond timestamps (13 digits) and human-readable dates. The default format for JavaScript Date.now() and modern JSON APIs.