Calculation Methodology

Last updated: July 26, 2026

How we implement, test, and document calculator logic.

Implementation

Tools run in the browser. We use focused calculation and processing logic, then test representative inputs and known expected results before publishing changes.

Formulas & sources

We select formulas and references that match the specific tool rather than applying one source list everywhere. Where assumptions differ by jurisdiction, profession, or school of thought, the tool explains the assumption and asks users to enter the relevant value.

Testing, updates & compatibility

We check normal, empty, boundary, and invalid inputs where practical. We update content when a calculation, source, or explanation needs correction, and record corrections through our published policy. Browser-based file tools also have size limits because available memory differs by device and browser.

Rounding & display

Results are rounded for readability. Currency shows 2 decimal places; percentages typically 1–2 decimals. Internal calculations use full floating-point precision before display rounding.

Assumptions you control

Interest rates, Nisab prices, exchange rates, and activity levels are entered by you — The Daily Tools does not fetch live market or commodity data.

Questions? See Sources Policy or Contact.