Unix Timestamp Converter
Convert Unix epoch timestamps to readable dates and back online, in seconds or milliseconds. Free and in your browser, no upload.
What this tool does
Turn a Unix timestamp into a human date, or a date into a timestamp. The converter detects seconds versus milliseconds automatically and shows the ISO, UTC, local and relative forms at once. A "Now" button fills in the current epoch. Everything runs in your browser, with no clock sent anywhere.
Building or debugging an API? Pair this with UUID Generator and JSON Formatter.
What you can use it for
- Read a timestamp from a log or database into a real date.
- Get the current epoch in seconds for an API call.
- Check whether a token expiry is in the past or the future.
- Convert a date into the timestamp a system expects.
How to use it
- Type a Unix timestamp to see the date forms it maps to.
- Or type a date to get the epoch in seconds and milliseconds.
- Use the "Now" button to grab the current timestamp.
- Copy any value with the button next to it.
Everything runs inside your browser. No file is uploaded to any server. See more tools in this field.
Pairs well with
Other tools people reach for in the same flow.
- UUID Generator and Validator
work with UUIDs
Strong fit in developer workflows.
- JSON Formatter and Validator
format and validate JSON
Strong fit in developer workflows.
- Base64 Encoder and Decoder
encode and decode Base64 text
Strong fit in developer workflows.
- JWT Decoder: Read Token Payload
decode a JWT header and payload
Strong fit in developer workflows.
- Number Base Converter
convert number bases
Strong fit in developer workflows.
Related tools
DeveloperCron Expression Generator and Parser
Build, parse and validate cron expressions for Unix, GitHub Actions, Vercel, Quartz and AWS EventBridge. See plain-language descriptions and the next run times. In your browser.
UUID Generator and Validator
Generate, validate and convert UUIDs online: v4, v5, v7, NIL and MAX. Instant and free, in your browser, no upload to any server.
JSON Formatter and Validator
Format, validate and minify JSON online. Beautify messy JSON or compact it in one click, free and entirely in your browser, no upload.
Base64 Encoder and Decoder
Encode and decode Base64 text online, with an optional URL-safe alphabet. Runs in your browser, nothing is uploaded to a server.
Frequently asked questions
Seconds or milliseconds, how does it know?
It uses the size of the number: values of about 1e12 or larger are read as milliseconds, smaller ones as seconds. That matches how almost every system stores epochs after the year 2001.
What time zone are the dates in?
The ISO and UTC lines are always in UTC, so they are unambiguous. The local line uses your browser time zone, and the relative line is phrased against the current moment.
What date formats can I paste?
Anything your browser understands, such as ISO 8601 like 2026-06-04T10:30:00Z, or common forms like 2026-06-04. If a date cannot be parsed, you will see a short error.
Can it handle dates before 1970 or far in the future?
Yes. A negative timestamp like -86400 points to the day before the Unix epoch, 31 December 1969, and very large values map to dates centuries from now. The converter reads negative and far-future epochs the same way as any other, so both resolve to a real date.
Can I convert a whole list of timestamps at once?
Not in a single paste. The converter focuses on one value so it can show every form at the same time, and it updates the moment you type. For a list, convert them one by one, copying each result before moving on to the next.