Timestamp Converter
How to use
Converts a Unix timestamp (in seconds or milliseconds) into a human-readable date, or converts any date back into a timestamp. Includes a "now" button to grab the current timestamp.
Unit
Unix Timestamp
Human Readable Date
- Decoding a Unix timestamp found in an API response or log file while debugging
- Generating a timestamp to hardcode into a test fixture or database seed
- Checking exactly when a JWT token was issued or will expire
- Converting a database record's created_at value into a readable date for a report
What a Unix timestamp counts, and what it deliberately ignores
A Unix timestamp is the number of seconds since 00:00:00 UTC on 1 January 1970. It carries no time zone, because it is not a time of day: it is an instant, and the same instant has a different local time everywhere. That property is exactly why timestamps are the right thing to store: converting an instant to a local time is always possible, while recovering an instant from a local time requires knowing the zone and the daylight-saving rules that applied on that date, which is information most systems throw away.
The count deliberately ignores leap seconds. Since 1972, twenty-seven leap seconds have been inserted into UTC to keep clock time aligned with the Earth's rotation, and Unix time skips them: a day is always exactly 86,400 seconds in this representation. This keeps arithmetic simple at the cost of a small, accumulating divergence from true elapsed time. For everything short of satellite navigation and high-frequency trading, that trade is the right one and the divergence never matters.
The two practical traps are magnitude and range. Unix time is defined in seconds, while JavaScript, Java and several databases work in milliseconds: feeding one into something expecting the other lands you in 1970 or in the year 56000, which is at least an obvious failure. Less obvious is the 2038 problem: a signed 32-bit timestamp overflows on 19 January 2038, and any system still storing one will wrap to 1901. Modern platforms use 64-bit values and are fine, but embedded devices, old file formats and legacy database columns are where the remaining exposure sits.
Free and private. Everything runs on your own device, with no account and no uploads.
Debugging an API response or database record often means staring at a Unix timestamp with no idea what date it represents. This tool converts timestamps (seconds or milliseconds) to human-readable dates and back.
Seconds-based timestamps are 10 digits for current dates, while millisecond timestamps are 13 digits, the toggle lets you pick the right one.
Yes, a "now" button fills in the current timestamp for testing or reference.
Dates display using your browser's local time zone by default, since Unix timestamps themselves are always UTC-based under the hood.
- 1
Paste a timestamp or pick a date
Enter a Unix timestamp, or use the date picker to go the other direction.
- 2
Choose seconds or milliseconds
Match the unit your timestamp is actually in to avoid a wildly wrong date.
- 3
Copy the converted value
Grab the human-readable date, or the timestamp, whichever direction you needed.
- ·Count the digits first, 10 digits means seconds, 13 means milliseconds, mixing them up gives a date decades off.
- ·Use the "now" button to quickly grab a fresh timestamp for testing expiry logic.
- ·Remember the display uses your local time zone, convert to UTC explicitly if you need to compare timestamps across regions.