Page type
Live interactive calculator
MarketInvoice and PeptideClear both have genuinely live calculators that recompute as you type. FundBiz's "calculator" pages are mostly static worked-example tables despite the name, a real gap worth closing before building the standard.
Genuinely live: change an input, the results panel updates immediately.
Gap. Static worked-example table, not an interactive calculator despite the name and URL.
Live, vanilla JS, recomputes on every keystroke, no framework, no build step.