Summary: A Free Timestamp Converter for Unix Time and Dates
A timestamp converter translates between a Unix timestamp, the count of seconds since 00:00:00 UTC on 1 January 1970, and a calendar date. Paste a number on the Unix → Date tab and the page shows it as ISO 8601, RFC 2822, an HTTP date and a readable date in any time zone. Switch to Date → Unix, enter a date, time and time zone, and it returns the timestamp in seconds and milliseconds. The unit (seconds, milliseconds, microseconds or nanoseconds) is detected for you.
It runs in your browser; nothing is uploaded (you can check the Network tab in DevTools). Formulas are simple: milliseconds = seconds × 1,000, and a day is 86,400 seconds. Leap seconds are not counted, as in Unix time itself.
Table of Use: Inputs and Results
| You enter | Read as | Result |
|---|---|---|
| 1700000000 (10 digits) | Seconds | 2023-11-14T22:13:20.000Z, which is 17:13:20 -05:00 in America/New_York |
| 1700000000000 (13 digits) | Milliseconds | The same instant as above |
| 1700000000000000 (16) or 1700000000000000000 (19) | Microseconds or nanoseconds | The same instant again, kept to the millisecond |
| 0 | Seconds | 1970-01-01T00:00:00.000Z, the Unix epoch |
| -86400 | Seconds, before the epoch | 1969-12-31T00:00:00.000Z |
| 2024-01-15 12:30:00 in Asia/Kolkata | Local clock time in that zone | 1705302000 seconds (07:00:00 UTC) |
| 2026-03-08 02:30:00 in America/New_York | A time skipped by daylight saving | 1772955000, moved forward to 03:30:00 -04:00, with a warning |
| 2026-11-01 01:30:00 in America/New_York | A time that occurs twice | 1793511000, the first occurrence (-04:00), with a warning |
| Format | Example | Common use |
|---|---|---|
| Unix seconds | 1700000000 | Databases, logs, JWT exp and iat claims |
| Unix milliseconds | 1700000000000 | JavaScript Date.now(), many web APIs |
| ISO 8601 (UTC) | 2023-11-14T22:13:20.000Z | JSON payloads, API responses |
| ISO 8601 with offset | 2023-11-14T17:13:20-05:00 | Showing local time without losing the instant |
| RFC 2822 | Tue, 14 Nov 2023 17:13:20 -0500 | Email Date headers |
| HTTP date (RFC 9110) | Tue, 14 Nov 2023 22:13:20 GMT | Last-Modified, Expires and Date headers |
Features of the Timestamp Converter
- Current time panel. It shows your local time with the Unix seconds and milliseconds, refreshed every second; Use current time and Use current date and time copy it into the fields.
- Unit detection by size, or choose Seconds, Milliseconds, Microseconds or Nanoseconds yourself.
- Forgiving input. Commas, spaces, underscores and apostrophes as thousands separators, a leading minus sign and a decimal point are accepted.
- Any time zone. The Time zone menu lists the zones your browser knows, starting with UTC, and begins on your own zone.
- Daylight saving handled. Skipped and repeated local times are flagged instead of silently guessed.
- Up to nine outputs with copy buttons, including a Relative to now line such as “in 26 days”.
It converts one value at a time. To add or subtract time, compare two timestamps or count down, use the Unix Timestamp Tool.
How to Use the Timestamp Converter
- For a timestamp, stay on Unix → Date and paste the number into Unix timestamp.
- Check the line that says what the number was read as; change Unit if it guessed wrong.
- For a date, click Date → Unix, then fill Date and Time. Seconds are supported, and a blank time counts as midnight.
- Choose the Time zone. On Date → Unix your entry is read as local time in that zone.
- Read the Converted Formats panel and click the clipboard button beside the value you need.
To compare clocks across cities, open the World Clock or the Time Zone Converter. For the gap between two dates, use the Date Difference Calculator, and for a running clock the Stopwatch or the Countdown Timer.
Who Can Use the Timestamp Converter
- Developers reading log lines, API payloads and token expiry values.
- Support and operations teams turning an event time into the customer's local time.
- Data analysts cleaning exports where dates arrive as epoch numbers.
- Students learning how computers store time.
Dates turn up in many diagnostic tools. Read the HTTP date headers returned by the HTTP Header Viewer, the validity window in the SSL Certificate Checker, or a domain's registration dates from the WHOIS Lookup, then convert them here. The Cron Expression Generator helps once you want to schedule something at that time.
FAQs: Timestamp Converter Questions
How do I convert a date and time to a Unix timestamp in a specific time zone?
Open the Date → Unix tab, enter the Date and Time, and pick the Time zone. The entry is read as local clock time in that zone, daylight saving included, so 12:30 on 15 January 2024 in Asia/Kolkata gives 1705302000, while the same clock time in UTC gives 1705321800. Copy the seconds or milliseconds value from Converted Formats.
How do I convert a Unix timestamp to ISO 8601?
Paste the number into Unix timestamp on the Unix → Date tab. ISO 8601 (UTC) shows the instant with a Z suffix, for example 2023-11-14T22:13:20.000Z for 1700000000. ISO 8601 in your chosen zone shows the same instant with an offset, such as 2023-11-14T17:13:20-05:00 in America/New_York. Both can be copied with the clipboard button.
How do I tell if a timestamp is in seconds, milliseconds, microseconds or nanoseconds?
Leave Unit on Detect automatically. Values under 100 billion are read as seconds, under 100 trillion as milliseconds, under 100 quadrillion as microseconds, and larger ones as nanoseconds, which matches 10, 13, 16 and 19 digits for current dates. A Read as line names the unit used. Results are exact to the millisecond; finer digits are dropped.
What is the difference between ISO 8601, RFC 2822 and the HTTP date format?
ISO 8601 writes the year first, such as 2023-11-14T17:13:20-05:00, and is standard in APIs and databases. RFC 2822 is the email Date style, such as Tue, 14 Nov 2023 17:13:20 -0500. The HTTP date, defined in RFC 9110, is always GMT and appears in headers such as Last-Modified and Expires. All three describe the same instant.
Why does the converter say a time does not exist or happens twice?
Daylight saving time causes both. When clocks spring forward, as at 2:30 a.m. on 8 March 2026 in America/New_York, that time never occurs, so the result is moved forward by the size of the jump and you are warned. When clocks fall back, as at 1:30 a.m. on 1 November 2026, the time occurs twice and the first occurrence is used.
Can I convert dates before 1970 or far in the future?
Yes. Dates before 1 January 1970 have negative timestamps, so type a minus sign: -86400 is 31 December 1969 in UTC. The supported range is that of a JavaScript Date, about 271,821 BC to AD 275,760. The Year 2038 problem affects systems that store time in a signed 32-bit integer, whose limit 2147483647 is 19 January 2038; this converter is unaffected.
Does Unix time include leap seconds?
No. Unix time counts every day as exactly 86,400 seconds and ignores leap seconds, and this converter does the same, so its results match what operating systems and programming languages produce. The converted-formats panel repeats that note under the time zone line.
Is it safe to paste timestamps and dates into this converter?
Yes. The conversion runs in your browser; nothing is uploaded (you can check the Network tab in DevTools) and nothing is stored. The only thing read from your device is its time zone name, used to preselect the Time zone menu, and the clock, used for the current-time panel and the Relative to now line.