23 tools · all run in your browser
Online calculators
Calculators for money, business, health and dates, each with the formula shown so you can check the result yourself. Results update instantly and nothing you type is stored.
Percentages4
- Percentage CalculatorWork out percentages of numbers, shares and changes.
- Percentage Increase CalculatorFind the % increase between two values or add X% to a value.
- Percentage Decrease CalculatorFind the % decrease between two values or subtract X%.
- Percentage Difference CalculatorCompare two values when neither is the reference.
Finance6
- Mortgage CalculatorEstimate mortgage payments, interest and payoff time.
- Loan CalculatorMonthly payment, total interest and amortization schedule.
- Compound Interest CalculatorSee how savings grow with compound interest and regular deposits.
- Investment CalculatorProject the growth of regular investments.
- Inflation CalculatorSee how inflation changes prices and purchasing power.
- Simple Interest CalculatorCalculate simple (non-compounding) interest.
Dates & time3
Health2
Commerce4
Tax1
Work & pay2
Travel1
Financial calculators use standard formulas: the amortising loan formula for loans and mortgages, and periodic compounding for interest and investments. They are estimates for planning purposes — lenders may apply fees, different day-count conventions or rounding rules.
Health calculators such as BMI and BMR give population-level estimates and are not a medical diagnosis.
Frequently asked questions
How accurate are the calculators?
Calculations use double-precision arithmetic and are rounded only for display. Financial results are estimates; always confirm with your bank or advisor before making decisions.
Can I see the formula?
Yes. Every calculator page explains the formula it uses in the 'How it works' section.