How to use this days until calculator
- Pick a date, choose your target date in the date box (a birthday, holiday, deadline or event), and optionally give it a name.
- Read the Days result, it shows how many days until that date, or how many days ago it was.
- Check the Weeks and Months figures and the status line, they update instantly as you choose.
- For a birthday or anniversary, tick "This is a yearly / recurring event", the count switches to the next occurrence of that month and day.
- Click "Save to my list" to keep that event in your saved list, then add more, they are shown together below sorted soonest first.
How it counts the days
The calculator takes today at local midnight and your chosen date at midnight, then works out the difference between the two in whole days. A future date counts up to the day it arrives, and a past date counts how long ago it was. To make the same number easier to picture, the result is also shown as weeks (days divided by 7) and approximate months (days divided by 30.44, the average length of a month over a year). The weeks and months are rounded to one decimal place, so they are a quick guide rather than exact calendar months.
Yearly and recurring events (birthdays, anniversaries)
Turn on "This is a yearly / recurring event" for a date that comes back every year, and the calculator stops counting to one fixed date. Instead it always counts down to the next occurrence of that month and day, this year if it has not happened yet, or next year if it has already passed, rolling over automatically the moment it does.
The 29 February edge case: a recurring event dated 29 February only has a real anniversary once every four years. In any year that is not a leap year, this calculator counts down to 28 Februaryof that year instead of skipping ahead to 1 March. That rule applies consistently every non-leap year, so a 29 February birthday always lands on the 28th when there is no 29th to land on.
Saving a list of events
Use "Save to my list" to keep a named event instead of tracking one date at a time. Add as many birthdays, deadlines and anniversaries as you like, each keeps its own date and its own yearly / recurring setting, and the whole list is shown together sorted soonest first. The list lives in your browser's local storage on this device only, so it is still there next time you open the page, but it is never uploaded anywhere. Clearing your browser's site data removes it.
Time zones and "today"
Because the tool uses your device's local date, the meaning of "today" follows whatever time zone your computer or phone is set to. That is what you want almost all of the time, but if you are counting toward an event in another part of the world, remember that midnight there may fall on a different calendar day. For a simple countdown to a personal date, your local date is exactly right.
Frequently asked questions
How many days until a date?
Pick your target date and the calculator counts the whole days between today and that date. A future date shows how many days until it, a past date shows how many days ago it was.
Does it count today or the target day?
The result is the number of nights between the two dates, so tomorrow shows 1 day and today shows 0. That is the standard way a countdown is measured.
Why are weeks and months rounded?
Weeks are days divided by 7 and months use the average month length of 30.44 days, both rounded to one decimal. They are a quick guide, not exact calendar months.
Which time zone does it use?
It uses your device clock and your local date, so "today" follows whatever time zone your computer or phone is set to.
How does the yearly / recurring event option work?
Turn it on for a birthday, anniversary or any other date that repeats every year. Instead of counting to one fixed date, the calculator counts down to the next occurrence of that month and day, and automatically rolls over to next year once this year's date has passed.
What happens to a recurring event dated 29 February?
In a year that is not a leap year, a recurring event set to 29 February counts down to 28 February of that year instead of jumping ahead to 1 March.
Can I track more than one date at a time?
Yes, use "Save to my list" to add a named event to your saved list. Add as many as you like, they are shown together sorted soonest first and stay saved in your browser between visits.
Is my saved list uploaded anywhere?
No, the saved list is stored only in your browser's local storage on this device. It is never sent to a server, and clearing your browser data will remove it.
What happens to a recurring event dated February 29?
In a year that is not a leap year, a recurring event set to February 29 counts down to February 28 of that year instead of jumping ahead to March 1.