Methodology & data sources

All calculations run entirely client-side in your browser. The page ships the formula and any required tables; nothing you enter is transmitted to a Kalcify server, persisted in a database, or shared with a third party. Open the browser dev tools on any tool page and you can read every line of arithmetic that produces your result.

Calculator logic is implemented from the textual rules of the originating authority (for example, the IRS publication that defines a tax bracket, the WHO classification that defines a BMI band, or the W3C specification that defines color-contrast). Numerical constants are taken from the most recent publication available at the time the page is built, and the page’s “last updated” timestamp reflects the most recent change to that data set.

Tax tools are reviewed at the start of each tax year for every supported jurisdiction and any time a mid-year change is published (rate cuts, threshold indexation, new levies). Health, web-standard and developer tools are reviewed when the underlying specification changes — typically every two to three years for WCAG, longer for WHO classifications.

Each tool page exposes its own “Last updated” timestamp directly above the calculator. That timestamp reflects when the data set or formula on the page was last modified, not just when the marketing copy changed.

Kalcify is informational. Tax calculators produce estimates, not filings. Health calculators are screening aids, not medical diagnoses. For decisions with material financial or medical consequences, consult a qualified professional in your jurisdiction. The full disclaimer lives in the Terms of Service.