Days Between Two Dates Calculator

Calculate the number of days, weeks, months and years between two dates online.

Formula

Days = |Date2 βˆ’ Date1|

The calculator computes the absolute difference between two dates in days, then converts to weeks, months and years accounting for leap years and varying month lengths.

Examples

About the Date Calculator

The Days Between Dates calculator computes the exact difference between two selected dates. Results are displayed simultaneously in days, weeks, full months, and full years β€” convenient for tasks ranging from vacation planning to contract deadline calculations.

All calculations account for leap years and varying month lengths (28–31 days). The calculator uses the standard Date API algorithm used in operating systems and databases.

This tool is useful for accountants calculating payment terms, HR managers counting tenure, and when processing loans, leases, and legal deadlines where the exact number of days has legal significance.

Benefits

Instant Calculation

Results update automatically when you select dates β€” no buttons or waiting. All calculations run locally in your browser.

Leap Year Support

The calculator correctly handles February 29 and varying month lengths. Results are always accurate β€” just like professional systems.

Four Units of Measurement

The difference is shown in days, weeks, months, and years simultaneously. Each value can be copied with one click for use in documents.

FAQ

What does the date calculator do?

The calculator computes the exact difference between two dates and shows the result in four units: days, full weeks, full months, and full years. The order of dates doesn't matter β€” the result is always positive.

Are leap years accounted for?

Yes, the calculator automatically accounts for leap years (366 days) and regular years (365 days). The calculation is based on the standard Date API, which correctly handles all calendar features.

Does the calculator count only working days?

No, the calculator counts all calendar days without exceptions. Calculating business days requires accounting for holidays and weekends of a specific country, which is beyond the scope of this tool.

What formula is used?

For days β€” the absolute difference in milliseconds divided by the number of milliseconds in a day (86,400,000). For months and years β€” counting full calendar periods considering the day of month.

How accurate is the calculation?

The calculator uses the browser's standard Date API, which correctly works with dates ranging from 100,000 BC to 100,000 AD. For practical tasks (20th–21st century dates), accuracy is absolute.