Inclusive vs exclusive — what’s the difference?

Exclusive counts full days strictly between the start and end (default). Inclusive adds 1 day, counting both endpoints. Example: Jan 1 to Jan 1 is 0 days exclusive, 1 day inclusive.

How are months and years calculated?

We use calendar-aware math: subtract years, then months, then days with borrowing based on the real length of each month. This mirrors how dates roll over on a calendar rather than dividing by average month lengths.

What do “business days” include?

Business days count Monday through Friday only. Public holidays are not excluded in this basic calculator and may reduce the actual number in your country.

Dates • Inclusive/Exclusive • Business days

Days between dates

Pick a start and end date. Toggle inclusive counting or business days (Mon–Fri). Optionally include time.

Ready.

Summary

Start—

End—

Totals

Days (exclusive)—

Calendar-aware difference

Years / months / days—

—
This uses calendar borrowing (real month lengths), not average months.

Notes

Business days ignore public holidays.
Times are optional; we compute in UTC internally to avoid DST issues and display using your locale.

About this days-between calculator

How it works

We build UTC timestamps from your inputs (prevents DST drift).
Exclusive counts full days strictly between dates; Inclusive adds 1 day.
Calendar Y/M/D uses real month lengths and proper borrowing.

Edge cases & limitations

Months vary in length; “1 month” follows calendar boundaries.
Business days = Monday–Friday only; holidays not excluded.
Partial days: totals are based on exact millisecond difference.

This tool is for educational use and general planning only.

Last updated: August 19, 2025

Days between dates

Results

Summary

Totals

Calendar-aware difference

Notes

About this days-between calculator

How it works

Edge cases & limitations

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