I made the same mistake twice, and the second time I decided to build something. Both times it was a notice period. I counted four weeks forward, told an employee their last working day, then found a public holiday inside that window. Wrong date. In employment law, that mistake costs someone a month's notice pay or opens a dispute. I looked at what already existed. Most tools were US-only, buried inside a bigger product, or so cluttered with ads that counting by hand was faster. None of them let you select a country and filter out its public holidays. So I built five calculators: count business days between two dates, add or subtract business days, work out a notice period end date, calculate a deadline date. All five pull from a live public holidays database covering 100+ countries. While building, I kept finding the same question across different communities. HR forums, finance threads, legal Q&As. Always some version of: is this calendar days or business days? Bank transfers, IRS refund timelines, Net 30 payment terms, court filing windows. The question never changed, the context did. The blog is working through each one now. Three more calculator tools are queued. HR and payroll affiliate integrations are next. If a country is missing or a public holiday looks wrong for your region, tell me below. I'm still adding coverage and I read every comment.

workingdayscalc

Count working days without counting days.

Count working days without counting days.