Calculator first
Every dedicated calculator page puts the interactive calculator before long explanations. Supporting content exists to clarify formulas, units, assumptions and limitations—not to pad pages with decorative copy.
Local by design
Calculator inputs are processed in JavaScript in your browser. No account or external calculation API is required. Optional recent history is stored in localStorage on your device.
Zero calculator dependencies
The calculator interface uses HTML, CSS, vanilla JavaScript, native Canvas and browser APIs without a framework, external font or chart library. Google Analytics is optional and loads only after analytics consent.
Quality before quantity
We prefer a smaller set of complete calculators over many thin variants. A calculator must have a distinct purpose, working logic, useful documentation and quality checks before it is published.
Scenario comparison and export
Calculator pages can compare up to three local scenarios, restore prior inputs, export current inputs and results as CSV, copy formulas and surface a compact live result dock on smaller screens. Favorites and recent-tool shortcuts make repeat calculations faster without requiring an account.