How do I calculate the number of days between two dates?

Subtract the earlier date from the later date to get the difference in milliseconds, then divide by 86,400,000 (milliseconds per day). Our calculator does this instantly for any two dates you enter.

Does the calculator include the start and end dates?

By default the calculator counts the days between the two dates exclusively (not including either endpoint). Toggle the 'include end date' option to count the end date as well — useful for calculating event durations.

How many days are in a year?

A common year has 365 days. A leap year has 366 days. The average year is 365.2425 days when accounting for the leap year cycle.

📆 Age

How Many Days Between Two Dates?

📅 Updated March 2026📆 Any date range🔢 Days, weeks, months & years

Enter any two dates to find the exact number of days between them — plus weeks, months, and years. Useful for countdowns, anniversaries, deadlines, and satisfying curiosity.

Start date

End date

Include end date in count Business days only (Mon–Fri)

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days

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Weeks

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Months

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Years

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Business days

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Quick calculations

Common Uses

Countdowns

How many days until your next birthday, a wedding, a vacation, or the end of a contract? Set your end date to the future event and the start date to today.

Looking back

How many days have you been with your partner? How many days since you started your job? Set both dates in the past for an exact count.

Business and legal

Contracts, notice periods, and deadlines are often measured in business days. Use the business days filter to exclude weekends from the count. Note that this calculator does not account for public holidays.

Age in days

Enter your date of birth as the start date and today as the end date to see your exact age in days. Or use our dedicated Age in Days calculator for more detail including day milestones.

Frequently Asked Questions

Subtract the earlier date from the later date. The calculator does this for you instantly, accounting for different month lengths and leap years. The result is expressed in days, weeks, months, and years.

By default the calculator counts the days between the two dates exclusively — not including either the start or end date. Check "Include end date" to add one day to the count, which is useful for things like event durations or contract lengths where the last day counts.

The business days count excludes Saturdays and Sundays. It does not exclude public holidays, as these vary by country and region. For legal or contract purposes, always verify with the relevant jurisdiction's rules.

A common year has 365 days. A leap year has 366 days. The average year is 365.2425 days accounting for the leap year cycle. This calculator correctly handles leap years in all calculations.

How Many Days Between Two Dates?

Common Uses

Countdowns

Looking back

Business and legal

Age in days

Frequently Asked Questions

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