Unix Timestamp Converter
Convert between Unix timestamps, ISO 8601, and human dates. Multi-timezone, multi-format, with relative time.
About the Unix Timestamp Converter
A Unix timestamp is a plain integer that counts seconds since January 1, 1970 UTC. It shows up in logs, database rows, API responses, and JWT expiry fields, and a value like 1720000000 tells you nothing at a glance. This tool turns that integer, a millisecond version, or a written date into a readable date, plus every format you might paste back.
Type a value into the input box. If it is 9 to 13 digits the tool reads it as a Unix timestamp, treating 10 digits or fewer as seconds and longer strings as milliseconds. Anything else goes to the browser date parser, so ISO 8601 and common date text also work. You get six rows covering seconds, milliseconds, ISO 8601, UTC, local, and relative time.
Everything runs in your browser, so the timestamp never leaves your machine. That matters when the value came from a production log or a customer record. There is no account, no upload, and no rate limit. A live epoch counter ticks at the bottom, and every output row copies to your clipboard with a single click.
How to use the Unix Timestamp Converter
- 1Type a Unix timestamp, millisecond value, or date string into the input field at the top.
- 2Or click Now (s), Now (ms), or Now (ISO) to load the current moment in that format.
- 3Pick a zone from the Timezone dropdown to control the Local row.
- 4Read the converted seconds, milliseconds, ISO 8601, UTC, local, and relative values in the results panel.
- 5Click any row to copy its value to your clipboard; a check mark confirms the copy.
What you can use it for
Reading server logs
A crash log records the failure at 1719849600. Paste it in, switch the Timezone dropdown to your team's zone, and read the exact wall-clock moment plus how long ago it happened, lined up against other reports.
Checking token expiry
A JWT payload shows an exp of 1720003200. Paste that number, use the Relative row to see whether the token is already past due, and read the exact cutoff in ISO 8601.
Coordinating across zones
You are scheduling a release with a teammate in Tokyo. Enter the planned UTC time, then flip the Timezone dropdown between Asia/Tokyo and your own zone to read the same instant in both and avoid an off-by-one-day slip.
Seeding test data
You need a fixed timestamp for a database fixture. Click Now (ms), copy the value from the milliseconds row, and paste a stable, unambiguous number into your seed script.
Seconds, milliseconds, and the epoch
A Unix timestamp counts the seconds since the Unix epoch, midnight UTC on January 1, 1970. It is a single UTC integer with no timezone attached, so the same number means the same instant everywhere. Timezone only matters when you convert back to a human date, which is why the Local row changes with the dropdown while the seconds and ISO rows stay put.
The catch is unit. Some systems store seconds and some store milliseconds, and the two differ by a factor of 1000. A ten-digit and a thirteen-digit number can point to dates decades apart if you guess wrong. This tool disambiguates by digit count and shows both forms side by side, so you can confirm which unit your source uses before trusting it.
Frequently asked questions
Does my timestamp get sent anywhere?
No. Conversion happens entirely in your browser. Nothing is uploaded and the values you enter are not logged. You can disconnect from the network and the tool keeps working, which helps when the timestamp came from a production log or a private record.
How does it know if my number is seconds or milliseconds?
By length. A 9 or 10 digit number is read as seconds and multiplied by 1000; an 11 to 13 digit number is read as milliseconds. Current second timestamps are 10 digits and millisecond timestamps are 13, so most values resolve correctly.
Why does my short number fail to convert?
Unix detection only fires for 9 to 13 digit numbers. A short value like 1000 falls outside that range and goes to the browser date parser, which may read it as a year or reject it. Below nine digits, paste a full date string instead.
Can I use a timezone that is not in the list?
The dropdown offers eleven common zones, from UTC through Los Angeles, Berlin, Kolkata, Tokyo, and Sydney. The tool opens on your browser's detected zone, but the selector is limited to those eleven. For another region, pick a listed zone that shares the same UTC offset.
What date formats can I paste in?
Besides raw numbers, you can paste anything the browser Date parser accepts. ISO 8601 like 2026-07-09T12:00:00Z is the most reliable. Formats such as Jul 9 2026 usually work, but ambiguous strings can be misread, so prefer ISO 8601 for exact results.