Unix Timestamp Converter
Convert epoch seconds or milliseconds to dates, or ISO dates back to Unix time, for one value or a whole list.
Drop your file hereTap to choose a file
or click to browse, or paste from the clipboard
Both directions, explicit units
Convert Unix seconds or milliseconds to a date, or an ISO 8601 date back to Unix time. You pick the unit yourself, so a 10-digit and a 13-digit value are never confused.
UTC and your local time
Every value is shown as Unix seconds, Unix milliseconds, an ISO 8601 time in UTC and the time in your own time zone. The tool reads that zone from your browser and names it with the result.
Batch conversion with export
Paste up to 2,000 values, one per line. An invalid line is flagged with its line number instead of stopping the batch. Copy the table for a spreadsheet or download it as timestamps.csv.
How to convert Unix timestamps
- 1
Choose the input format: Unix seconds, Unix milliseconds or ISO date with offset.
- 2
Paste one value per line, or select Use current time for an example.
- 3
Select Convert timestamps and check the Error column for any line that could not be read.
- 4
Select Copy table to paste into a spreadsheet, or Download CSV.
What people use this tool for
- Read the timestamps in application logs, token claims or API responses.
- Turn a column of epoch values from a database export into dates for a spreadsheet.
- Get the Unix time for a deadline or release date to use in code or a query.
- Check whether two systems disagree because one writes seconds and the other milliseconds.
Frequently Asked Questions
How do I convert a Unix timestamp to a date?
Leave Input format on Unix seconds, or choose Unix milliseconds, paste the value and select Convert timestamps. The table shows the same instant as seconds, milliseconds, a UTC time in ISO 8601 form and your local time. Use current time fills in the present moment and converts it.
Is my value in seconds or milliseconds?
Count the digits. Present-day timestamps have 10 digits in seconds and 13 in milliseconds: 1700000000 and 1700000000000 are the same instant, 14 November 2023 at 22:13:20 UTC. If the result lands in January 1970, you converted seconds as milliseconds. If it lands tens of thousands of years in the future, you did the opposite.
How do I convert a date to a Unix timestamp?
Choose ISO date with offset and enter the date as 2026-01-02T13:30:00Z, or with a numeric offset such as 2026-01-02T17:30:00+04:00. Seconds and up to three decimal places are optional. A date without Z or an offset is rejected, because the same clock time is a different instant in every time zone.
Which time zone is the local time in?
The one your browser reports, named in the status line after each conversion, for example Europe/London. Daylight saving time is applied for the date in question. The tool cannot display a third time zone. To check one, convert to UTC here and apply that zone's offset.
Does it support dates before 1970 or after 2038?
Yes to both. Negative values count back from 1 January 1970, so -86400 is 31 December 1969. The year 2038 limit applies to systems that store time as a signed 32-bit number, which ends at 2147483647. This tool is not bound by it and accepts any instant a browser date can represent.
Can I use fractional seconds, microseconds or nanoseconds?
Seconds can carry up to three decimal places, such as 1700000000.123, and milliseconds must be whole numbers. Microsecond and nanosecond timestamps, which have 16 and 19 digits, are not supported directly. Remove the last three digits of a microsecond value, or the last six of a nanosecond value, and convert the rest as milliseconds.
Why is a line marked invalid?
Each line must hold exactly one value in the selected format. Typical causes are a thousands separator, a unit suffix, quotation marks copied from a log, a date with a space instead of T, or a calendar date that does not exist, such as 30 February. The Error column explains each case, and the other lines are still converted.
What are the limits, and is anything uploaded?
A batch can hold 2,000 lines and 200,000 characters. The page displays the first 100 rows, while the copied table and the CSV contain every row. All conversion happens in your browser with its own time zone data, and nothing is sent anywhere.