caldays
Working-day calculator

Business days between two dates for 206 countries.

Count working days between any two dates, excluding weekends and that country's public holidays. The same engine that powers our MCP server — 206 countries, years 2020–2030, no signup.

Result for United States
21 working days
31 total days · 23 weekdays · 8 weekend days · 2 holidays excluded
Holidays excluded (2)
Friday, 19 Jun 2026 — Juneteenth
Friday, 3 Jul 2026 — Independence Day (obs.)
How it works

Per-country public holidays, automatic

Pick any of 206 countries and we subtract that country's national holidays (and joint cuti bersama, in Indonesia's case) from the date range. Holidays that fall on a Saturday or Sunday are ignored — they don't reduce working days because the weekend already excluded them.

Same engine that powers the caldays MCP server (mcp.caldays.com) used inside Claude. Data covers years 2020–2030 and is curated from official government sources (SKB 3 Menteri for Indonesia, OPM for the US, gov.uk for the UK, etc).

Limitation in v1: weekends are Saturday–Sunday for every country. Countries with a Friday–Saturday weekend (Saudi Arabia, UAE, Egypt, Israel) are NOT yet supported as a different weekend pattern — we'll add this soon.

Frequently asked questions

Does this include the start and end date?
Yes — the range is inclusive on both ends. A start date of June 1 and end date of June 5 covers 5 days, not 4.
What counts as a public holiday?
National public holidays as published by each country's government. For Indonesia, we also include cuti bersama (joint leave) — these reduce working days for civil servants and most companies. For other countries, "joint" types are excluded unless they're statutory.
Why not just call your MCP server?
You can — install caldays as a Claude connector at /claude and ask "How many business days between …". This page is the same calculation in a browser-friendly form.
Can I do the reverse — add N business days?
Use the MCP add_business_days tool inside Claude. A dedicated web form for this is on the roadmap.

Explore more

United States · holidays excluded
21 working days