# Unix Timestamp Converter

URL: https://speedycalculator.com/calculators/conversion/unix-timestamp/
Last updated: 2026-10-25

> The Unix timestamp converter turns a date and time in any time zone into seconds (and milliseconds) since 1 January 1970 UTC, and turns any timestamp back into a readable date, ISO 8601 string and relative time. Everything is calculated in your browser; nothing you type is sent to our server.

## Inputs

- Convert
- Date and time
- Unix timestamp
- Time zone

## Results

- Unix time (seconds)
- Milliseconds
- ISO 8601 (UTC)
- In the chosen time zone
- Relative to now

## Formula

```
timestamp = seconds elapsed since 1970-01-01 00:00:00 UTC (leap seconds ignored)
```

## Explanation

Unix time is how computers, databases, logs and APIs store moments in time. It counts seconds since the “epoch” at midnight UTC on 1 January 1970 and is the same everywhere on Earth, regardless of time zone.

### How to use the Unix Timestamp Converter

- **Convert**
- **Date and time**
- **Unix timestamp**
- **Time zone**

Everything runs in your browser, so results appear instantly and nothing you type is sent to a server.

### How it works

Dates are converted using your browser’s time-zone database, which handles daylight saving time. Timestamps with 13 or more digits are treated as milliseconds.

## Worked example

Inputs — Convert: Timestamp → date & time; Unix timestamp: 1767225600; Time zone: UTC / GMT / Zulu.

Results — **Unix time (seconds) = 1767225600**; Milliseconds = 1767225600000; ISO 8601 (UTC) = 2026-01-01T00:00:00.000Z; In the chosen time zone = Thu, 1 Jan 2026, 00:00:00 (UTC+00:00); Relative to now = 297 days ago.

## Key terms

- **Epoch**: 00:00:00 UTC on 1 January 1970, time zero for Unix time.
- **ISO 8601**: International date format, e.g. 2026-01-01T00:00:00Z.

## FAQ

**What is the 2038 problem?**
32-bit signed timestamps overflow at 03:14:07 UTC on 19 January 2038.

**Does Unix time include leap seconds?**
No, every day is treated as exactly 86,400 seconds.

**Seconds or milliseconds?**
JavaScript and many APIs use milliseconds (13 digits); Unix tools use seconds (10 digits).

**What formula does the Unix Timestamp Converter use?**
timestamp = seconds elapsed since 1970-01-01 00:00:00 UTC (leap seconds ignored).