Business days calculator
Weekends come out automatically. Holidays are a field rather than a guess, because they differ by country, state and industry.
Inclusive counting, and why holidays are manual
This counts both endpoints, which is the convention for delivery windows and notice periods — Monday to Friday is five working days, not four. That differs deliberately from the days-between calculator, which measures the gap.
Holidays are entered by hand on purpose. A built-in list would have to pick a country, and would then be wrong for everyone else, quietly and invisibly. Regional holidays, company shutdown days and industry-specific closures all vary, and a calculator that silently assumed US federal holidays would mislead most of the people using it. Counting the holidays in your range takes a moment and the answer is then actually correct.
The working-hours line assumes an eight-hour day, which is a reasonable default for project planning but obviously not universal.
Questions
Are both dates included?
Yes. Monday to Friday counts as five working days. If you want the gap rather than an inclusive count, the days between dates calculator does that.
Why isn't there a holiday list built in?
Because holidays are regional, and a built-in list would be wrong for most visitors without saying so. Counting the ones in your range keeps the answer honest.
What about half days or four-day weeks?
This assumes Monday to Friday. For a compressed week, count the extra non-working days into the holidays field.