Weeks until a date
Pick any date and instantly see how many weeks away it is - plus the remaining days.
How the weeks are counted
The tool counts whole days from the start of today to the start of the date you pick, then splits them into full weeks and the days left over. Weeks are always rounded down: 30 days shows as 4 weeks and 2 days, never as 5 weeks. Today counts as day zero, so tomorrow is 0 weeks and 1 day away. Dates in the past show a message instead of a negative number.
Why plan in weeks
Most of life runs in weekly cycles: work sprints, school timetables, training plans, cleaning rotas. "8 weeks" tells you something "56 days" does not: you have eight Mondays to make progress, eight weekends to rest. It is also the natural unit for anything that ramps up gradually, from marathon training to learning a language.
Weeks in common periods
| Period | Weeks |
|---|---|
| A month | About 4.3 (28 to 31 days) |
| A quarter | About 13 |
| A year | 52 weeks and 1 day (2 days in a leap year) |
| A pregnancy, from the last period | About 40 |
Some years have 53 ISO weeks rather than 52; the ISO week number tool explains why. For pregnancy dates, use the dedicated due date calculator.
How long does a new habit take?
People often quote 21 days, but the best-known study points to longer. In 2009, Phillippa Lally and colleagues at University College London followed people building a new daily habit and found it took a median of 66 days, a little over nine weeks, for the behavior to feel automatic, with a wide range from 18 to 254 days (European Journal of Social Psychology). If you are building a habit toward a date, give yourself the weeks. A habit tracker widget keeps the streak in view in the meantime.
Count down in weeks on your Home Screen
In Left, add the date as an Ahead countdown and set Show as... to Weeks. The widget then shows weeks left at a glance; see the countdown widget page.
Questions
How many weeks until a date?
Pick the date above. The tool shows the full weeks and remaining days from today, plus the total number of days.
Does the tool round weeks up or down?
Down. It shows full weeks plus the days left over, so 30 days is 4 weeks and 2 days.
How many weeks are in a year?
52 weeks and 1 day in a 365-day year, or 52 weeks and 2 days in a leap year. Some years have 53 ISO weeks.
Can I show a countdown in weeks on my iPhone?
Yes. In Left, add the date as an Ahead countdown and set Show as... to Weeks, then add an Ahead widget to your Home Screen or Lock Screen.
Start noticing what matters.
Download Left on your iPhone to see the time you have left, dates you are looking forward to, build the habits you want to keep, and become a better version of yourself.
Scan or search "Left" on the App Store.