Pick two dates and read the difference as calendar days, a years/months/days breakdown and weeks — with an include-end-date toggle, per-weekday counts and a business-days line. Or add and subtract days, weeks, months or years from a date with the end-of-month rule stated.
Privacy ledger
Data acquired
None.
Libraries used
Lit 3 — bundled into the tool file itself.
Data stored
None.
Data transmitted
None.
Use it on your own page
Download the tool as a single self-contained HTML file: readable source with the Lit library included, zero network requests — it works opened straight from your disk, and you can customize everything.