Weeks Between Dates Calculator
Count the exact number of weeks and remaining days between two dates, with an option to count working weeks that exclude Saturdays and Sundays.
Enter both dates in the date pickers above.
What is the Weeks Between Dates Calculator?
The ByteTools Weeks Between Dates Calculator counts how many whole weeks separate two dates, plus the leftover days.
- Whole weeks plus remainder days, and decimal weeks
- Working-weeks mode that excludes weekends
- Total day count and inclusive day count
- DST-safe UTC day arithmetic
- Handles reversed date ranges with a signed result
- Completely private — runs in your browser
How to use the Weeks Between Dates Calculator
- 1
Choose the start date.
- 2
Choose the end date (it can be before the start — the result is signed).
- 3
Read the answer in whole weeks plus remaining days.
- 4
Switch on working weeks to exclude Saturdays and Sundays.
- 5
Check the decimal weeks and total days figures underneath.
About the Weeks Between Dates Calculator
The ByteTools Weeks Between Dates Calculator counts how many whole weeks separate two dates, plus the leftover days. Pick a start and an end date and you get the answer as weeks and days, as a decimal number of weeks, and as a total day count — the three ways people usually need it.
It is handy for pregnancy tracking, project sprints, training plans, notice periods, rental terms and school terms. There is also a working-weeks option that counts only Monday to Friday, which converts the span into business weeks of five days for planning and invoicing.
The day count is done on UTC calendar days rather than local timestamps, so daylight saving transitions inside the range cannot shift the answer by one. Everything is calculated in your browser and nothing you enter is uploaded.
Frequently asked questions
How many weeks are between two dates?
Divide the number of days between them by seven. The whole part is the number of complete weeks and the remainder is the extra days, so a 45-day span is 6 weeks and 3 days. This tool shows both that breakdown and the decimal equivalent.
Does the calculator include the start and end date?
The main count is the gap between the two dates, so a Monday-to-Monday range is exactly one week rather than eight days. An inclusive day count that counts both endpoints is shown separately if that is what you need.
What is a working week in this tool?
A working week is five days, Monday to Friday. In working-weeks mode the calculator counts only weekdays in the range and then divides by five, which is how project schedules and notice periods are usually expressed.
How many weeks are in a year?
There are 52 weeks and 1 day in a common year, and 52 weeks and 2 days in a leap year. That extra day is why a fixed calendar date lands on a different weekday each year, and why the ISO calendar occasionally contains a 53rd week.
Can I count weeks backwards from a future date?
Yes. If the end date is earlier than the start date the result is shown as a negative span with the same weeks-and-days breakdown, which is useful for working backwards from a deadline or a due date.
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