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Tools & documentation

THE TIME TOOLBOX

ISO 8601 Converter

Convert an API date to a Unix timestamp, taking its UTC offset into account.

Accepted format: complete date and time with Z or ±HH:MM. Up to 9 fractional digits.

RESULTS
Date in the selected time zone—
UTC date—
ISO 8601 · UTC—
Timestamp · seconds—
Timestamp · milliseconds—

An offset changes the representation, not the instant

2024-04-01T14:00:00+02:00 and 2024-04-01T12:00:00Z represent the same instant: 1711972800 Unix seconds. The Z suffix denotes UTC.

Which subset of ISO 8601 is accepted?

This tool accepts complete calendar dates with a time, seconds and an explicit offset, commonly used in APIs and close to RFC 3339. Date-only values, ISO weeks, ISO durations, leap seconds and strings without an offset are rejected to avoid silently assuming an interpretation.

A fixed offset such as +02:00 is not a geographical time zone: Europe/Paris switches between +01:00 and +02:00 depending on the date. In RFC 3339, the −00:00 suffix indicates an unknown local offset; the tool calculates the UTC instant without inferring a location.

Reference: RFC 3339