Unix Timestamp Converter
A Unix timestamp is just a count of seconds since January 1, 1970 — every system uses it internally, but no human reads it directly, so this converts it straight to a readable date and time.
Inputs
Result
Sat, 25 Jul 2026 17:20:00 GMT
2026-07-25T17:20:00.000Z
How the unix timestamp converter works
The timestamp is treated as seconds since the Unix epoch (January 1, 1970, 00:00:00 UTC), multiplied by 1,000 to convert to milliseconds for standard date construction, then formatted as a readable UTC date and time.
Worked example: timestamp 1785000000
- 1,785,000,000 seconds after January 1, 1970 UTC converts to a specific date and time in 2026.
- The result is shown both as a readable UTC string and in ISO 8601 format for programmatic reference.
Common mistakes to avoid
Entering a timestamp in milliseconds instead of seconds
Unix timestamps are conventionally in seconds, but some systems (notably JavaScript's own Date.now()) work natively in milliseconds — entering a millisecond-based timestamp here without dividing by 1,000 first produces a wildly incorrect, far-future or invalid date.
Assuming the result is automatically in your local time zone
The output here is shown in UTC — for a timestamp's equivalent time in a specific local time zone, that UTC offset would need to be applied afterward using something like the Time Zone Converter.
Frequently asked questions
Why does Unix time start counting from January 1, 1970 specifically?
It's an arbitrary but now deeply entrenched convention chosen early in Unix's development — it predates most systems still using it today, but changing the reference point now would break enormous amounts of existing software, so it has remained the universal standard.
How can I tell if a timestamp is in seconds or milliseconds just by looking at it?
A seconds-based timestamp for current dates is typically a 10-digit number (like 1785000000), while the same moment in milliseconds would be a 13-digit number — the digit count is a quick visual clue.
Will Unix timestamps eventually run out or overflow?
A commonly cited concern is the 'Year 2038 problem', affecting older systems that store timestamps as 32-bit signed integers — those specific systems will overflow in 2038, though most modern systems now use larger integer types that push this limit far into the future.
Why is this format used instead of just storing a readable date directly?
A single number is simpler and more efficient for computers to store, compare, and calculate durations with than parsing and manipulating a formatted date string — the readable format is purely for human convenience at the display layer.
Related calculators
Time Zone Converter
Convert a local time across UTC offsets.
Add Days Calculator
Add or subtract days from a date.
Date Difference Calculator
Days, weeks and months between any two dates.
Countdown Calculator
Time remaining until an important date.
Time Duration Calculator
Hours and minutes between two times.