Free online calculators
A free suite of well-designed everyday calculators — fast, deterministic, and explained. No ads, no signup.
Finance
Tip CalculatorCompute tip, total, and per-person split for any party size.Loan CalculatorCompute monthly payment, total interest, and total paid for any loan term.Compound Interest CalculatorProject savings growth over time, optionally with recurring monthly contributions.Discount CalculatorCompute final price and savings from a percent-off or flat discount, with optional sales tax.
Health
BMI CalculatorCompute your body mass index in metric or imperial, with category and healthy range.Running Pace CalculatorCompute running pace, time, or distance — give any two and we compute the third.TDEE CalculatorCompute Total Daily Energy Expenditure (TDEE) and BMR using the Mifflin-St Jeor equation.
Productivity
Percentage CalculatorThree modes: X% of Y, X is what % of Y, or percentage change between two numbers.Age CalculatorCompute exact age in years, months, and days between any two dates.Date CalculatorCount working days or days between two dates, or add and subtract days from a date.GPA CalculatorCompute weighted and unweighted GPA on the US 4.0 scale, with optional honors and AP/IB bonus points.
Conversions
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