MonsiTools

Spreadsheets break when you just want one quick answer, and most calculator sites only do the sums someone else picked. MonsiTools lets you type a formula in plain words and get a working calculator, then chain calculators into a workflow so each answer feeds the next step, for example price to margin to break-even to cash runway. There are over 1,300 ready-made calculators for business, finance, ecommerce, health and everyday maths, usable without an account. Developers and AI assistants can run the same calculators through a JSON API and an MCP server.