Weeks Calculator: Add, Subtract, Between Dates

To use weeks calculator, choose any option, such as adding or subtracting weeks to a specific date, or seeing the number of weeks between two dates. For example, adding 4 weeks to January 1, 2025, will give you January 29, 2025. Subtracting 3 weeks from March 10, 2025, will give you February 17, 2025.


1 week
There are 1 week and 0 days from July 17, 2025 to July 24, 2025.

Steps To Use the Weeks Calculator

  1. Select Operation: Choose any one option according to your requirement, like Add Weeks, Subtract Weeks, or Weeks Between using the radio buttons at the top. However, by default it is selected Weeks Between.
  2. Enter Values:
    • For Weeks Between: Select a Start Date and an End Date. The calculator will show you the total weeks. The initial result is 1 week between two dates.
    • For Add Weeks: Select a starting Date" and enter number of Weeks to add. The calculator will show the future date.
    • For Subtract Weeks: Select a starting Date and enter number of Weeks to subtract. The calculator will show the past date.
  3. Dates: All date fields are editable, click on and use the date picker or type a date in `YYYY-MM-DD` format.
  4. Calculate: Click the Calculate button to perform the calculation and see the results. .
  5. Results:
    • The main result is displayed in a large font.
    • The descriptive sentence below provides more context about weeks calculation.
  6. Clear Button: Click Clear to reset all input fields and the result display to the default Weeks Between calculation.

Note: The maximum number of weeks for addition or subtraction is 5220, approx 100 years. The calculations take into account different lengths of months and leap years.

Weeks Between Dates Calculation:

To calculate the number of weeks between two dates, you can use the following formula:

Weeks = (End Date − Start Date) ÷ 7

Days = Difference ÷ (1000 × 60 × 60 × 24)

Then, Weeks = Days ÷ 7

This is how you can use the formula to calculate the number of weeks between two dates.

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