# Epoch Converter

An epoch converter for Unix timestamps: a timestamp to a date and back, in seconds, milliseconds, microseconds or nanoseconds. Nothing is uploaded.

Canonical page: https://filetity.com/epoch-converter

## Capabilities

- Free: Yes, with no watermark and no page limit.
- Account required: No. There is no account system.
- Processed on device: Yes. The file is read by your browser and never uploaded. There is no server to send it to.
- Formats: A timestamp in seconds, milliseconds, microseconds or nanoseconds. Out as ISO 8601, RFC 1123, your own timezone and the day of the week.
- Limits: Dates outside the range a JavaScript date can hold, about 273,000 years either side of 1970, are reported rather than guessed at. That almost always means the unit is wrong.
- Mobile: Yes, on any modern mobile browser. Large files are limited by the memory the phone gives the browser.
- Offline: Yes, once the page has loaded. The tool keeps working with no network connection.

## Questions

### How do I know if my timestamp is seconds or milliseconds?

Count the digits. Around now a timestamp in seconds has ten and one in milliseconds has thirteen, with microseconds at sixteen and nanoseconds at nineteen. That is the only signal a bare number carries, and it is what this page uses, though you can override it.

### Why does my date come out in 1970 or in the year 56000?

The unit is wrong. Reading milliseconds as seconds multiplies the date by a thousand and lands you tens of thousands of years out; reading seconds as milliseconds divides it and puts you a few days after 1970. Switch the unit and the date will look sensible immediately.

### Is a date with no timezone read as mine or as UTC?

As UTC, deliberately. JavaScript reads a bare date as UTC and a bare date with a time as local, which means two nearly identical strings behave differently, and that is how people end up hours out. Both are read as UTC here. Add an offset such as +05:30 to be explicit.

### Why does the page not show a live clock?

Because a relative line that updates while you are reading it moves under you, and because reading the clock during a render is impure. The current time is read when you press the button, and the result is anchored to that moment.

### What is the epoch, and why 1970?

Unix time counts seconds from midnight UTC on 1 January 1970, which is simply when the convention was set at Bell Labs. There is nothing significant about the date; it was recent when it was chosen, and everything since has inherited it.

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