How does the calculator handle leap years?

The calculator automatically accounts for leap years. February 29th is included in leap years (years divisible by 4, except century years that are not divisible by 400).

Can I add or subtract months and years?

Yes, you can add or subtract any combination of years, months, days, hours, minutes, and seconds. The calculator handles month length variations automatically.

How accurate are the calculations?

The calculations are highly accurate and account for leap years, varying month lengths, and daylight saving time changes. Results are precise to the second.

Can I calculate business days?

Currently, the calculator works with calendar days. For business day calculations, you would need to manually account for weekends and holidays.

How do I handle time zones?

The calculator works with the time you input. For time zone conversions, you should first convert to your desired time zone, then perform the calculation.

Can I calculate recurring events?

Yes, you can use the calculator to determine dates for recurring events by adding the appropriate time interval to your start date.

Date Time Calculator

Calculate the number of days between two dates or add/subtract time from a date. Free online date calculator for project planning and scheduling.

Date Difference

Start Date

End Date

Include end date in calculation

Add/Subtract Time

Initial Date

Operation

Time to Add/Subtract

Years

Months

Days

Hours

Minutes

Seconds

Frequently Asked Questions

Common questions about date and time calculations.

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Last updated: 2025-10-21 — Compiled and reviewed by Calvin (Date & Time Research, FreeCalculators.app)