Date Difference Calculator

Worked example

1 January to 11 January — 10 days

Quick answer

Are both endpoint dates counted?

No. The calculator returns the elapsed difference between the two dates.

What is the Date Difference Calculator?

Find the absolute number of days and weeks between two calendar dates. Use it when you have the required inputs and want a deterministic, repeatable result with the calculation method visible.

How to use this calculator

Enter the values requested by the tool, keep units and time periods consistent, resolve any validation message, calculate, then review the primary answer together with the displayed formula and supporting values.

Formula and method

This calculator uses a deterministic formula and shows the calculation breakdown with the result so the answer can be checked.

Worked example

1 January to 11 January 10 days

Common mistakes to avoid

Check units, decimal points, percentages, signs, date/time order, selector choices, and rounding. For important decisions, verify the result against an independent source or qualified professional when appropriate.