Some commands allow the user to specify a date, e.g.:
Many date formats are valid. Here are some examples:
Lastly, there is Mercurial's internal format:
This is the internal representation format for dates. The first number is the number of seconds since the epoch (1970-01-01 00:00 UTC). The second is the offset of the local timezone, in seconds west of UTC (negative if the timezone is east of UTC).
The log command also accepts date ranges: