205 calculators · 6 categories
Every number, calculated properly.
Loans, calories, percentages, paint, GST, break-even — 205 free calculators that show the formula, the assumptions and where the data comes from. No signup, no ads, nothing leaves your browser.
205 CALCULATORS0 ADS100% IN-BROWSER
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Six groups, each with the tools people actually search for.
Financial
Loans, savings, interest and inflation — the numbers behind a decision.
25 CALCULATORSHealth & fitness
BMI, calories, body fat and hydration, using published formulas.
20 CALCULATORSMath
Percentages, areas and shapes — with the formula shown, not just the answer.
44 CALCULATORSEveryday
Age, dates, tips, discounts and units. The small sums you do weekly.
73 CALCULATORSHome & construction
Paint, tiles, concrete and bricks — quantities before you order.
23 CALCULATORSBusiness
GST, margins, break-even and hourly rates for small operators.
20 CALCULATORSMost used
Start with the ones that pay for themselves.
Loan CalculatorMonthly instalment, total interest and total repayment for any loan.
BMI CalculatorBody mass index with the WHO category and healthy weight range.
Percentage CalculatorX% of Y, what percent X is of Y, and percentage increase or decrease.
GST CalculatorAdd or remove GST at any rate, with base and tax split.
Paint CalculatorLitres of paint for walls and ceilings, by coats and coverage.
Age CalculatorExact age in years, months and days on any date.
Calorie NeedsBMR and daily calories with an activity multiplier (Mifflin-St Jeor).
Tile CalculatorTiles and boxes needed, with cutting wastage.