Data methodology

BusinessDayKit separates source data, calculation rules, and explanatory copy so business calendar results can be reviewed.

Holiday source

U.S. federal holiday records are based on the U.S. Office of Personnel Management federal holiday schedule. Each record includes a date, holiday name, source label, source URL, and last-verified date. When a holiday is observed on a nearby weekday, the observed date is the date used by the business-day calculators.

Business-day rule

A counted business day is a Monday through Friday date that is not removed by the selected holiday calendar. The default U.S. planning mode excludes listed U.S. federal holidays. Weekday-only counts are also shown on annual and monthly pages so users can see how many days were removed by holiday exclusions.

Daily pages

Daily status pages use the default calendar timezone of America/New_York. The date is generated by code during the build process, and the page displays the relevant month, current business-day status, and next listed federal holiday when one is available in the current data set.

Invoice date tools

Invoice tools calculate calendar due dates from the invoice date and selected terms, such as Net 30. If a business-day adjustment is enabled, the result moves forward until it lands on a counted business day. This adjusted date is for planning and follow-up; the invoice or agreement should control the actual payment term.

AI and automation boundary

Automation may generate data files and deploy pages. AI may assist with short explanatory copy, but it is not the source for dates, counts, holiday records, or policy conclusions. Factual values should come from source data or deterministic calculations.