Methodology

Design principles

1. One clear job per tool — inputs, action, result.
2. Client-side first — compute in the browser when possible.
3. Show assumptions — especially for tax, finance, health, and legal estimates.
4. Label estimates — never imply official government or medical outcomes.

Finance & tax tools

Indian tax and finance calculators reference published slabs and rules from the Income Tax Department and standard financial formulas (EMI, SIP, compound interest, etc.). When rates change for a new financial year, we update the underlying logic and the "Updated" date on the tool page.

Health tools

BMI and related calculators use established formulas with widely cited reference ranges. They are educational only — not a diagnosis.

Developer & text tools

Formatters and validators implement standard specifications (JSON, JWT structure, cron syntax, etc.). Invalid input should produce a clear error — never silent wrong output.

Report an issue

If a result looks wrong, use the feedback option on the tool page (where available) or reach out via our About page. Include the tool name, inputs used, and expected vs actual result.