What format does this parser accept?

It accepts ISO-8601 extended date-time strings: YYYY-MM-DD optionally followed by T and a time hh:mm:ss with optional fractional seconds, and an optional timezone of Z or ±hh:mm.

How does it handle the timezone offset?

It reports the offset exactly as written (Z, or a signed ±hh:mm), and separately computes the absolute UTC instant by applying that offset, so you can see both the local wall-clock fields and the universal time.

What if the string has no timezone?

A string with no timezone designator is ambiguous. The parser still extracts the fields but notes that the offset is missing, since the instant cannot be pinned down without it.

Does it validate the date?

Yes. It uses a strict regular expression for structure and then checks the ranges of each field (month 1–12, valid day for the month, hour 0–23, and so on) before reporting success.

Is my date sent anywhere?

No. Parsing happens entirely in your browser with a local regular expression and the Date API. Nothing is uploaded.

ISO-8601 Date-Time Parser

ISO-8601 strings pack a full date-time and timezone into a single token like 2026-06-06T14:30:00+01:00. This parser pulls that token apart so you can inspect every field individually — invaluable when debugging an API response, a log line, or a date that “looks right but isn’t”. Everything is computed locally in your browser.

How it works

The parser matches the string against a strict ISO-8601 regular expression that captures each component:

^(\d{4})-(\d{2})-(\d{2})(?:[T ](\d{2}):(\d{2})(?::(\d{2})(?:\.(\d+))?)?(Z|[+-]\d{2}:\d{2})?)?$

Each captured group is then range-checked: the month must be 1–12, the day must be valid for that month and year (including the leap-year rule for February), the hour must be 0–23, and minutes and seconds 0–59. Once the fields pass validation, the tool also computes the absolute instant by handing the string to the Date API, giving you the UTC date-time and epoch seconds.

Example

Parsing 2026-06-06T14:30:00.250+01:00 yields:

Field	Value
Year	2026
Month	06
Day	06
Hour	14
Minute	30
Second	00
Fraction	250
Offset	+01:00

The same instant in UTC is 2026-06-06T13:30:00.250Z, because the +01:00 offset means local time is one hour ahead of UTC.

Tips and notes

A trailing Z (Zulu) is equivalent to an offset of +00:00.
If the offset is missing, treat the time as “local to some unknown clock” — pin it down before doing arithmetic.
The wall-clock fields and the UTC instant differ by exactly the offset; comparing the two is a quick sanity check.