Date Calculator

Calculate the number of days, weeks, and months between two calendar dates or add/subtract years, months, and days online for free.

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How to use Date Calculator

  1. 1

    Choose your calculation mode: "Days Between Two Dates" or "Add/Subtract Days from a Date".

  2. 2

    Select the input dates and enter the number of days, weeks, or months to add/subtract.

  3. 3

    View the resulting calendar date, total day count, and breakdown.

Why use this tool?

Days Between Dates Calculator

Find the exact number of days, weeks, and months separating any two historical or future dates.

Date Addition & Subtraction

Calculate project deadlines, contract end dates, or warranty expirations by adding days to a date.

Working Days & Weekend Stats

See total calendar days as well as business weekdays and weekend days included in the interval.

Continue your workflow

Determine chronological age and days lived from a birthdate. Calculate exact age.

Exclude weekends to calculate business turnaround times and project schedules. Count working days.

Create a real-time live countdown timer for upcoming events and deadlines. Countdown to future dates.

Frequently asked questions

Can I calculate dates spanning across leap years and centuries?

Yes. The calendar engine handles dates across multiple centuries with full Gregorian calendar accuracy.

How do I calculate a project deadline that is 90 days away?

Select "Add to Date", choose today as the start date, enter 90 in the days field, and see the exact deadline date.

Can I include or exclude the end date in the count?

Yes. You can toggle whether the final day is included in the total day count.

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