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Epoch / Unix Timestamp Converter

Convert a Unix timestamp to a date and back — in UTC, unambiguously.

What you provide

Result

1700000000 = 2023-11-14 22:13:20 UTC

Read as Unix seconds. Everything is shown in UTC, so it reads the same for everyone regardless of timezone.

Diagnostic telemetry
Unix seconds
1700000000
Unix milliseconds
1700000000000
UTC
2023-11-14 22:13:20 UTC
ISO 8601
2023-11-14T22:13:20.000Z
Day of week
Tue

What this cannot tell you

  • Everything is shown in UTC so the answer reads the same for everyone. Your local time depends on your timezone and is deliberately not the headline figure.
  • A bare number is read as seconds unless it is large enough to only make sense as milliseconds. If yours is ambiguous, include units or a date.

Take this with you

This tool never saves runs. What it handles should not be written to disk — not even your own.

How this calculation works

A Unix timestamp counts the seconds since 1 January 1970 UTC. Enter one and the tool shows the date in UTC and ISO 8601; enter a date and it gives you the timestamp. A bare number is read as seconds unless it is too large to be anything but milliseconds.

What the results mean

Unix seconds
The standard timestamp — seconds since the 1970 epoch. What most systems mean by "a Unix timestamp".
Unix milliseconds
The same instant in milliseconds. JavaScript and many APIs use this; it is 1000× the seconds value.
UTC
The date and time in Coordinated Universal Time — the same for everyone, which is why it is shown rather than your local time.

Frequently asked questions

Is my timestamp in seconds or milliseconds?

Seconds timestamps are about 10 digits right now; milliseconds are about 13. This tool reads a bare number as seconds unless it is large enough that only milliseconds make sense. If yours sits near the boundary, include the units or paste a date to be sure.

Why show UTC instead of my local time?

Because a timestamp is a single instant, and only UTC describes it without ambiguity. If the tool used your local timezone silently, you and a colleague elsewhere would get different-looking answers for the same timestamp, which defeats the point.

Put this on your own site

Free to embed, no attribution required beyond the source link the frame carries itself. It runs entirely in your visitor's browser, sets no cookies and loads no third-party script.

Embed code
<iframe src="https://runthetests.com/embed/epoch-converter/" width="100%" height="560" style="border:1px solid #e5e5e5;border-radius:8px" title="Epoch / Unix Timestamp Converter" loading="lazy"></iframe>

Preview it at https://runthetests.com/embed/epoch-converter/. Embedded pages are marked noindex, so yours stays the canonical copy — not this one.

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