About this tool
Counting days by hand goes wrong at month boundaries, and it goes wrong more often when the two dates are months apart. Thirty-one, twenty-eight, thirty — by the third month you have lost track. Type both dates in and the count comes out the same every time, along with the weeks-and-days version, which is easier to hold in your head when you are planning around it.
The one decision worth making carefully is the counting option. Excluding the end date measures the distance between two days, which is what a deadline question asks. Including both dates counts the days themselves, which is what a leave application or a stay at a hotel asks. The difference is always exactly one day, and it is always the one day that matters.
Both dates are treated as plain calendar dates rather than timestamps, so the result cannot slide by a day because of a timezone setting. The whole calculation runs in your browser. Nothing about the dates you type leaves the page.
How to use this tool
- Set the start date. Both date fields open on today, so if you are counting forward from now you only need to change one of them.
- Set the end date. It has to be on or after the start date. Put them the other way round and you get a clear error rather than a negative number.
- Choose how to count. “Exclude the end date” is the default and gives the gap between the two days. “Include both dates” adds one, which is what you want when you are counting days of leave or days of an event.
- Read the result. The total in days, and the same figure again split into weeks and leftover days.
What this tool does not do
- It does not count working days, and it knows nothing about public holidays.
- It does not add or subtract a number of days from a date. It only measures the gap between two dates you supply.
- It ignores times of day, so a gap is always a whole number of days.
- Gregorian dates only.
Common questions
Which counting option do I want?
If the question is “how long until”, exclude the end date: from the 1st to the 8th is seven days. If the question is “how many days am I away”, include both dates: the 1st to the 8th is eight days, because you were away on both. The wrong choice here is where almost every off-by-one comes from.
Does it skip weekends and holidays?
No. Every day between the two dates counts. There is no working-day mode, partly because holiday lists differ by state and by employer and a wrong one is worse than none.
Why does it not give me months and years?
Because a month is not a fixed number of days and the answer would need a rule about what counts as a month. The age calculator applies that rule properly — use it if you need years, months and days.
Can my timezone change the answer?
No. Both dates are read as calendar dates in UTC, so the count is the same whether the page is open in Kochi or in Canada.
What does the weeks line mean?
It is the same total divided by seven: whole weeks, then the days that do not make up another week. 45 days shows as 6 weeks and 3 days.