# Data : Dates & Times \[ [ISO 8601](https://en.wikipedia.org/wiki/ISO_8601) | [RFC 3339](https://datatracker.ietf.org/doc/html/rfc3339) — a "profile" of ISO 8601 ] ###### Dates ``` YYYY-Www 1970-W12 week YYYY-Www-D 1970-W12-3 week + weekday YYYY-DDD, YYYYDDD 1970-123, 1970123 ordinal date YYYY-MM-DD, YYYYMM 1970-01-01, 19700101 calendar date YYYY-MM 1970-01 month ``` ###### Times Requires `T` prefix in ambiguous contexts. ``` hh:mm:ss.sss, hhmmss.sss 12:34:56.789, 123456.789 hh:mm:ss, hhmmss 12:34:56, 123456 hh:mm.mmm, hhmm.mmm 12:34.567, 1234.567 hh:mm, hhmm 12:34, 1234 hh.hhh 12.345 hh 12 ``` ###### Time Zones Default is local time. ``` Z UTC ±hh:mm, hhmm -05:00 EST ±hh -05 EST ```