Common uses
Contract notice periods, rental durations, pregnancy weeks, visa stays and event countdowns all need clean day counts — this handles leap years automatically.
Days Between Dates Calculator
Count days between two dates, with inclusive totals, weekday counts and weekend counts.
Enter your details and press Calculate to see results.
Formula
elapsed = end − start in UTC milliseconds ÷ 86,400,000; inclusive adds 1
Example
Jan 1 → Jan 31 is 30 days difference, 31 days inclusive.
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Frequently asked questions
Is the start day itself counted?
Difference mode excludes both endpoints' boundaries cleanly; switch to inclusive when a lease or trial includes its final day.
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