Timestamp converter. Epoch to human, both ways.
Conversions are computed locally in your browser, no upload, no server.
Epoch → human date
Auto-detects seconds vs milliseconds, microseconds or nanoseconds by magnitude.
Enter an epoch above to see the date.
Date → epoch
Pick a date & time, interpreted in your local timezone.
A timestamp converter turns a Unix epoch, the count of seconds since 1 January 1970 UTC, into a readable date, and turns a date back into that count. This one runs in your browser, shows Local, UTC and ISO 8601 at once, and reads 10, 13, 16 or 19 digits as seconds, milliseconds, microseconds or nanoseconds.
How to use the Timestamp Converter
This converter turns a Unix timestamp into a readable date and a date back into a timestamp. It works out the unit from the number of digits, so seconds, milliseconds, microseconds and nanoseconds all convert without a setting. Use it to read times in logs, API responses, databases and tokens, or to get the epoch for a date you need.
Step by step
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Check the live clock
The top card shows the current Unix time in seconds, ticking every second, with your local date and the value in milliseconds under it. Press Copy seconds or Copy ms to copy the current value, or Use as input to put it in the converter below.
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Convert a timestamp to a date
In Epoch → human date, paste a number into Unix timestamp. Use digits only; a minus sign in front gives a date before 1970. The line under the box says which unit it detected.
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Copy the format you need
The result lists Local, UTC, ISO 8601, Seconds and Milliseconds. Press the copy icon at the end of any row to copy that value.
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Convert a date to a timestamp
In Date → epoch, use the Date & time picker. It starts at the current time and reads what you pick in your device's time zone. The Seconds and Milliseconds boxes update, each with its own copy icon, and a UTC line underneath confirms the instant.
Reading the result
- The unit comes from the digit count: up to 12 digits is read as seconds, 13 to 15 as milliseconds, 16 to 18 as microseconds and 19 or more as nanoseconds. Present day values have 10, 13, 16 and 19 digits.
- For example, 1716239022 is detected as seconds. UTC shows Mon, 20 May 2024 21:03:42 GMT and ISO 8601 shows 2024-05-20T21:03:42.000Z.
- Local is the same instant in your device's time zone and language, so it reads differently on another device. UTC and ISO 8601 are the same everywhere.
- The round chip under the results gives a rough distance from now, such as 2 years ago or in 3 days. It counts a month as 30 days and a year as 365 days.
Tips and common mistakes
- If a date lands in 1970 or thousands of years ahead, the number is in a different unit from the one you expected. Check the detected unit line first.
- Store and send UTC or ISO 8601 values. Copy the Local row only for reading.
- The picker uses your own time zone. If the time you have is in UTC or another zone, convert it to your local time before you pick it, or the epoch will be off by the offset.
- Microsecond and nanosecond values are rounded to the nearest millisecond, so the Milliseconds row drops the extra precision.
Privacy and limits
Every conversion runs in your browser and nothing is sent anywhere or saved. The copy buttons use your browser's clipboard and fall back to an older copy method if needed. Values far outside the range JavaScript dates support show an out of range message instead of a date.
Everything an engineer needs.
- Convert epoch to date: paste any Unix timestamp and see Local, UTC and ISO 8601 formats instantly.
- Convert date to epoch: pick a date and time to get the matching Unix timestamp in seconds and milliseconds.
- Auto-detect the unit: the tool recognizes seconds, milliseconds, microseconds and nanoseconds by magnitude, no dropdown to fiddle with.
- See relative time: know at a glance whether a timestamp is “5 minutes ago” or “in 2 days”.
- Copy the live epoch: grab the current Unix time in seconds or milliseconds with one click.
- Use current time as input: press “Use as input” to pre-fill the epoch field with the present moment.
Everything runs on your device. Once the page has loaded, each conversion works without a connection, and the values you paste never reach a server. There is no account, no sign-up and no usage limit.
Four digit counts, one instant.
The tool never asks which unit you pasted. It counts digits instead: 10 digits is seconds, 13 is milliseconds, 16 is microseconds and 19 is nanoseconds, the magnitudes a present-day epoch has in each unit. The line under the input says which unit it detected, so a wrong guess is visible before you copy anything.
| Digits | Unit | Example value | Reads as (UTC) |
|---|---|---|---|
| 10 | seconds | 1716239022 | 20 May 2024, 21:03:42 |
| 13 | milliseconds | 1716239022000 | 20 May 2024, 21:03:42 |
| 16 | microseconds | 1716239022000000 | 20 May 2024, 21:03:42 |
| 19 | nanoseconds | 1716239022000000000 | 20 May 2024, 21:03:42 |
Here is why the check matters, worked from the tool's own rule. Read 1716239022000 as seconds and the date lands in June of the year 56,355. Read 1716239022 as milliseconds and it lands on 20 January 1970. Both are the same instant, 20 May 2024 at 21:03:42 UTC, once the unit is right.
The seconds count itself is defined by POSIX, in section 4.16 of the Open Group Base Specifications: a value that approximates the seconds elapsed since 1 January 1970 UTC, with every day counted as exactly 86,400 seconds. Stored as a signed 32-bit integer it runs out at 2147483647, which is 19 January 2038 at 03:14:07 UTC.
This tool uses JavaScript's Date object, which covers about 100 million days on either side of 1970, so 2038 is not a limit here. A 19-digit nanosecond value is divided down to milliseconds before conversion, which is why it still resolves to the right date.
UTC, local or ISO 8601: which row to keep.
Keep the UTC or ISO 8601 row when the value goes into a database, a log or an API, and read the Local row only for yourself. Local output depends on the device's zone and on daylight saving, so the same epoch prints differently in New York and New Delhi. The epoch itself has no zone at all.
The ISO 8601 row is what JavaScript's toISOString() returns: a 24-character string such as 2024-05-20T21:03:42.000Z, always in UTC, with the Z marking a zero offset. That shape is also a valid RFC 3339 timestamp, which the RFC describes as a date and time format for use in Internet protocols.
The date picker on the right works the other way around. The browser reads what you pick as local time, converts it through the device's zone and prints the epoch in seconds and milliseconds, with the UTC form underneath as a check. The Local row is formatted by Intl.DateTimeFormat, the browser's own formatter, which is why its wording follows your device language.
If you are building the API that emits these values, send epoch seconds or RFC 3339 with an offset, never a bare local string. That is the whole point of the UTC row. Our API development and integration services page explains how we scope that kind of work, and the time zone converter handles the case where your source time is already in another zone.
Frequently asked questions.
What does a timestamp converter do?
It translates between a Unix epoch, the number of seconds since 1 January 1970 UTC, and a date a person can read. Paste the number to get the date in Local, UTC and ISO 8601 form, or pick a date to get the number back. This one also tells you which unit it detected.
How do I convert a UTC timestamp to a readable date?
Paste the epoch into the Unix timestamp field. The UTC row shows the date with a zero offset, and the ISO 8601 row shows the same instant as 2024-05-20T21:03:42.000Z. Copy either one with the button beside it. The Local row is the same moment in your device's own time zone.
How do I turn a time into a timestamp?
Pick the date and time in the picker on the right. The browser reads it in your local time zone and prints the epoch in seconds and in milliseconds, with a UTC line underneath so you can confirm the zone. If the time you have is written in UTC, shift it to your local zone before you pick it.
Why does the tool read 13 digits as milliseconds?
Because a present-day epoch has 10 digits in seconds, 13 in milliseconds, 16 in microseconds and 19 in nanoseconds. The tool counts digits instead of asking because the unit is almost never written beside the number. The line under the input names the unit it chose, so a wrong read is visible at once.
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