Date & Time Tools
Free date and time tools: Unix timestamp converter (epoch to date), time zone converter, world clock, date calculator, ISO 8601 parser, and time ago. Convert timestamp to date in your browser, no signup.
8 tools · 100% browser-based · No uploads · No signup
About these Date & Time tools
Free date and time tools to convert timestamps, time zones, and date formats in your browser. The Unix timestamp converter turns epoch time into a human date (and the other way). Convert time zones, check a world clock, add days with the date calculator, parse ISO 8601, see “time ago”, or get Excel and RFC date formats.
Unix time is always UTC. A 10-digit number in the 2020s is usually seconds. A 13-digit number is milliseconds. Mixing those up is the usual “year 57000” bug. These pages do not call a time API; they use this device’s clock.
Tools in this category
Unix Timestamp Converter
Ten digits is seconds. Thirteen is milliseconds.
Time Zone Converter
Time zone converter online. Convert a time between New York, London, Tokyo, and any city. Free timezone converter in your browser.
ISO 8601 Date Converter
ISO 8601 converter online. Parse ISO dates and durations like P3DT4H. Free ISO 8601 date format tool.
Date Calculator
Date calculator online. Add or subtract days, weeks, or months from a date. Free add days to date tool.
Time Ago
Time ago calculator online. Convert a timestamp into "3 hours ago" or "in 2 days". Free relative time converter.
World Clock
World clock online. See the current time in UTC, New York, London, Tokyo, and more. Free world clock.
Duration Calculator
Duration calculator online. Find the time between two dates. Free date difference and elapsed time calculator.
Date Format Converter
Date format converter online. Get ISO, RFC 2822, Unix, Excel serial, and more from one date. Free date format tool.
How these tools run in your browser
The timestamp converter guesses seconds vs milliseconds from digit length. Time zone conversion uses the zone list in your browser. World clocks tick from this device, not from a world-time server. Convert → Time is a duration unit converter (hours to milliseconds). These Date & Time pages convert calendar dates and epochs.
Common Use Cases
- Convert a Unix timestamp to a date from a log or JWT
- Convert a meeting time between New York, London, and Tokyo
- Add 14 days to a start date
- See the current time in several cities
- Get ISO, RFC 2822, and Excel serial for one instant
Common Mistakes
Frequently Asked Questions
Paste the number into Unix Timestamp Converter. You get UTC, local time, and ISO. 10 digits are seconds; 13 digits are milliseconds.
Open Time Zone Converter, paste a time (or “now”), and pick cities. Offsets include daylight saving for that date.
No. Convert → Time turns 3600000 ms into hours. These pages turn timestamps and ISO strings into calendar dates and time zones.
No. Times are formatted on this device. If your computer clock is wrong, the world clock is wrong.