About Business Days HQ
Business Days HQ is a free independent tool built and operated by Kyle Bell as his separate personal business. Its purpose is to make business days planning easier to inspect, with visible inputs, assumptions and worked examples.
You can use the calculator without an account. Calculations happen locally in your browser. The guides explain the reasoning, including when a convenient shortcut does not apply.
Editorial approach
Guides are original explanations with primary sources where applicable. Manufacturer information is used for named products, calendar rules are identified as a particular preset, and estimates are not presented as professional project design. Formulas are checked with worked examples and validation cases before publication.
How this site is supported
This website is intended to be supported by advertising. Google advertising may appear when eligible. Advertising does not change the calculator’s formulas or examples. Named brands and source links are informational references, not endorsements or paid recommendations.