About KindCalc

KindCalc is a small library of everyday calculators: pay, loans, tips, percentages, BMI, dates, units, time zones, GPA, writing stats, passwords, color contrast, and QR codes. There are 15 tools in this first wave. Each page is a working calculator plus an explanation of the formula, examples, and limits.

We built the site because search results for simple math are crowded with pages that hide the tool under pop-ups or ship your inputs to a server. Every KindCalc calculator runs in your browser. We do not need your salary, birth date, or draft essay to show you a number.

The project is operated as a useful, ad-supported site. After Google AdSense approval, pages may show a small number of ads placed away from buttons and results. Ads should never be the product. If a page is wrong, tell us.

KindCalc is not a bank, tax preparer, university registrar, or clinic. Money and health tools include disclaimers because a clean formula is still not advice about your life.