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milliseconds to epoch

Milliseconds to Epoch Converter

JavaScript gives you epoch milliseconds, and so do most modern APIs. This converter reads 13-digit values as milliseconds automatically — no more guessing whether a number is seconds or milliseconds.

converter

One timestamp, every format.

Convert epoch time to dates and back. Precision auto-detected, timezone your choice.

Dates below render in the timezone above. Press / to focus the field.

Deep-link any timestamp with ?ts=1722750000

Why timestamps come in milliseconds

The original Unix timestamp counts seconds since the epoch, but seconds are too coarse for modern software. Nearly every platform that runs in a browser or an event loop measures time in milliseconds since January 1, 1970 UTC:

  • JavaScript — Date.now() and event.timeStamp return epoch milliseconds.
  • Java — System.currentTimeMillis() and Instant.now().toEpochMilli().
  • C#/.NET — DateTimeOffset.UtcNow.ToUnixTimeMilliseconds().
  • REST APIs, SDKs, and analytics events frequently ship 13-digit millisecond values.

How the converter auto-detects the unit

Because seconds and milliseconds are only three digits apart, a bare number is easy to misread. This tool detects the precision from the number of digits:

  • 10 digits — seconds (e.g. 1722750000).
  • 13 digits — milliseconds (e.g. 1722750000123).
  • 16 digits — microseconds (e.g. 1722750000123456).

If a value is ambiguous, lock the unit manually with the sec / ms / µs buttons. The result panel always shows the instant in every unit, so you can see at a glance which unit your source value uses.

Example conversions

  • 1767225600000 (ms) → January 1, 2026 00:00:00 UTC.
  • 1722750000123 (ms) → August 4, 2024 05:40:00 UTC with 123 ms.
  • 1750000000000 (ms) → June 15, 2025 15:06:40 UTC.

Notice how 1722750000 and 1722750000123 refer to the same instant — the digits line up and the tool shows both readings so you never have to re-paste to check.

Milliseconds to date in your own code

For one-off values, paste them here. For scripts, the conversions are one line:

  • JavaScript: new Date(1767225600000).toISOString() → 2026-01-01T00:00:00.000Z
  • Python: datetime.fromtimestamp(1767225600000 / 1000, tz=timezone.utc)
  • Java: Instant.ofEpochMilli(1767225600000L)
  • C#: DateTimeOffset.FromUnixTimeMilliseconds(1767225600000)

Gotchas with millisecond timestamps

  • Dropping the last three digits silently turns milliseconds into seconds — a date about 56,000 years in the future. Always keep all 13 digits.
  • JavaScript new Date(1722750000) interprets the argument as milliseconds, so a seconds value passed directly lands in 1970. Multiply by 1000 first.
  • Beware floating-point drift when converting microseconds — divide by 1000, don't round mid-way, and keep microseconds as integers where possible.
  • Fractional seconds: 1722750000.123 is 123 milliseconds past the whole second — the converter preserves the fraction in its milliseconds column.

Related tools

If your values are in seconds, use the Unix timestamp to date converter; to go the other direction, see the date to epoch converter. For decoding whole lists of mixed-precision timestamps, the batch converter handles one per line and exports TSV/CSV.

First published · Last reviewed · Maintained and developed by the Real Epoch Converter team · [email protected] · Contact · Methodology

Sources & references

More timestamp tools

Need the reverse direction, another precision, or a whole list at once? The epoch time converter on the home page converts dates to Unix timestamps and back — seconds, milliseconds, or microseconds — with batch conversion, and the Unix timestamp to date converter handles one value at a time.

Prefer reading? The guides explain Unix time, timestamp formats, and common bugs in depth, and the methodology page documents exactly how this site handles negative timestamps, fractional seconds, leap seconds, and daylight-saving transitions.

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