Numbers you can trust, answers in seconds.
16 calculators across finance, health, education, and everyday math, each with the formula, a worked example, and a plain-language explanation behind the number.
16 calculators, zero guesswork
Finance
Mortgage Calculator
Monthly payment, total interest, and full amortization, in seconds.
Open calculatorLoan Calculator
Monthly payment and total interest for any personal or auto loan.
Open calculatorCompound Interest Calculator
See how your savings or investment grows with compounding.
Open calculatorEveryday Math
Percentage Calculator
Percent of a number, percentage change, and percentage difference.
Open calculatorDiscount Calculator
Final price, amount saved, and stacked discounts, instantly.
Open calculatorAge Calculator
Exact age in years, months, and days, from any two dates.
Open calculatorUnit Conversion Calculator
Convert length, weight, temperature, and volume instantly.
Open calculatorDate Calculator
Days between two dates, or add and subtract time from any date.
Open calculatorTime Calculator
Add, subtract, or find the duration between two times.
Open calculatorEducation
Health & Fitness
BMI Calculator
Body Mass Index with WHO category and a healthy weight range.
Open calculatorCalorie Calculator
Daily calorie needs for maintaining, losing, or gaining weight.
Open calculatorPregnancy Due Date Calculator
Estimated due date and current week, from your last period or conception date.
Open calculatorBody Fat Calculator
Estimate body fat percentage using the US Navy method.
Open calculatorIdeal Weight Calculator
A healthy target weight range based on your height and frame.
Open calculatorFormula shown, not hidden
Every calculator shows its exact formula and a worked example, not just a black-box number.
No sign-up, no clutter
No accounts, no paywalls, no pop-ups between you and the answer.
Built for speed
Lightweight pages with no bloat, so every calculator loads and responds instantly.
Guides & explainers
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