taskwarrior-2.x/docs/src/time.md

Timestamps

Times may be specified in a wide variety of convenient formats.

• RFC3339 timestamps, such as 2019-10-12 07:20:50.12Z
• A date of the format YYYY-MM-DD is interpreted as the local midnight at the beginning of the given date. Single-digit month and day are accepted, but the year must contain four digits.
• now refers to the exact current time
• yesterday, today, and tomorrow refer to the local midnight at the beginning of the given day
• Any duration (described below) may be used as a timestamp, and is considered relative to the current time.

Times are stored internally as UTC.

Durations

Durations can be given in a dizzying array of units. Each can be preceded by a whole number or a decimal multiplier, e.g., 3days. The multiplier is optional with the singular forms of the units; for example day is allowed. Some of the units allow an adjectival form, such as daily or annually; this form is more readable in some cases, but otherwise has the same meaning.

• s, second, or seconds
• min, mins, minute, or minutes (note that m not allowed, as it might also mean month)
• h, hour, or hours
• d, day, or days
• w, week, or weeks
• mo, or months (always 30 days, regardless of calendar month)
• y, year, or years (365 days, regardless of leap days)

ISO 8601 standard durations are also allowed. While the standard does not specify the length of "P1Y" or "P1M", Taskchampion treats those as 365 and 30 days, respectively.