API Design · Junior · Question 21 of 75

How should dates and times be represented in a JSON API?

1As locale-formatted strings like 03.11.2026 15:30
2As Unix timestamps in some fields and strings in others
✓Correct answer: As ISO 8601 / RFC 3339 strings with a time zone, e.g. 2026-11-03T14:30:00Z

Explanation

A standard, unambiguous format avoids time zone bugs. Pick one style and use it everywhere.

Further reading

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