Date Formats

Dates are used as values in several HTTP headers. The proper format for a date is as follows:

Tue, 21 May 2002 12:34:56 GMT

Consider this format in parts:

  • First three characters of the day of the week, followed by a comma and a space

  • Two-digit day of the month (01-31), followed by a space

  • First three characters of the month, followed by a space

  • Four-digit year, followed by a space

  • Two-digit hour (0-23), followed by a colon

  • Two-digit minute (0-59), followed by a colon

  • Two-digit second (0-59), followed by a space and then GMT

This format allows for a date that is universally understood (GMT), unambiguous (no confusion between month and day or which century a year refers to), and of a fixed-length for easier dissection.

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