RootUtils

Date Difference

Client-Side Secure

Free online Date Difference Calculator. Calculate the exact number of days, weeks, or months between two dates. Simple, fast, and secure tool.

Result

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Date Calculator: Days Between Dates & Business Days

Calculate the duration between two dates in days, weeks, months, and years. Or use the Business Days mode to exclude weekends and calculate work days for project planning.

Need to know what date it will be in 90 days? Use the Add/Subtracttool to project future deadlines instantly.

Work Days

Standard business day calculation excludes Saturdays and Sundays. Perfect for calculating payroll periods, shipping estimates, and project timelines.

Age Calculator

Enter your birth date as the "Start Date" and today as the "End Date" to see your exact age in years, months, and days (e.g., 25 years, 3 months, 12 days).

Precise Duration

Our algorithm handles leap years (29 days in Feb) and varying month lengths (30 vs 31 days) correctly, ensuring 100% mathematical accuracy.

Frequently Asked Questions

Does this include the end date?

The standard calculation is exclusive of the start date and inclusive of the end date, which matches how most humans count "days from now". E.g., Today to Tomorrow is 1 day.

How are leap years handled?

We use the native JavaScript Date object, which has built-in knowledge of the Gregorian calendar, including leap years. If your range includes Feb 29th, it is counted.