How does it tell seconds from milliseconds?

By magnitude: 13-digit values are milliseconds, 10-digit are seconds. Timestamps near the boundary (before 2001 in ms) can be forced with the unit toggle.

Seconds elapsed since 1970-01-01 00:00:00 UTC, not counting leap seconds. It's the timestamp format of most logs, databases, and APIs.

Unix Epoch Interval Calculator

The exact span between two timestamps.

Timestamp ATimestamp B

A → 2025-01-01 00:00:00 UTC

B → 2025-07-22 00:00:00 UTC

Interval

202 d 0 h 0 min 0 s

17,452,800 seconds

Seconds

17,452,800

Minutes

290,880

Hours

4,848

Days

202

Weeks

28.86

hh:mm:ss

4848:00:00

Two epoch timestamps from a log file: how far apart are they? Paste them in seconds or milliseconds (auto-detected by magnitude) and get the interval as a full breakdown, plus each timestamp decoded to a human date.

How to use it

1.Paste two Unix timestamps (seconds or milliseconds).
2.Check the decoded UTC dates shown for each.
3.Read the interval as a breakdown and in every unit.

Questions people ask

How does it tell seconds from milliseconds?: By magnitude: 13-digit values are milliseconds, 10-digit are seconds. Timestamps near the boundary (before 2001 in ms) can be forced with the unit toggle.
What is Unix time?: Seconds elapsed since 1970-01-01 00:00:00 UTC, not counting leap seconds. It's the timestamp format of most logs, databases, and APIs.

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