Fast, accurate calculators for finance, health, math, and more — no signup required.
CalculatorsApp provides 30+ fast, free, and accurate online calculators for finance, health, math, and everyday use. No account or signup required — just open the page and start calculating. All tools work on mobile and desktop.
Financial Calculators
Our mortgage calculator uses the standard amortization formula to estimate monthly payments based on loan amount, interest rate, and term length. The compound interest calculator shows how savings and investments grow over time with daily, monthly, or annual compounding. Use the loan calculator to break down any personal, auto, or student loan into monthly repayments and total interest paid. The income tax calculator, salary calculator, and retirement calculator help you plan your finances at every stage of life.
Health Calculators
The BMI calculator uses the World Health Organization formula (weight ÷ height²) to classify body weight — supporting both metric (kg/cm) and imperial (lbs/in) inputs. The calorie calculator uses the Mifflin–St Jeor equation to estimate your daily caloric needs based on age, weight, height, and activity level. Additional tools include body fat percentage, BMR (Basal Metabolic Rate), target heart rate, water intake, and pregnancy due date.
Math & Everyday Tools
The percentage calculator instantly handles percentage of a value, percentage change, and reverse percentage. The scientific calculator supports trigonometry, logarithms, exponents, and memory functions. Everyday tools include a unit converter (length, weight, temperature, volume, speed), GPA calculator, grade calculator, date difference calculator, fuel cost calculator, discount calculator, and currency converter with automatic geo-detection.
Frequently Asked Questions
How is a mortgage payment calculated? Monthly payment M = P × [r(1+r)^n] / [(1+r)^n − 1], where P is the principal, r is monthly interest rate, and n is number of payments.
What is a normal BMI? A BMI of 18.5–24.9 is considered a healthy weight. Under 18.5 is underweight; 25–29.9 is overweight; 30 and above is obese, per WHO classification.
How does compound interest differ from simple interest? Simple interest is calculated only on the original principal. Compound interest is calculated on the principal plus all previously earned interest, producing exponentially greater returns over time.
Are the calculators free? Yes — 100% free with no account, no subscription, and no hidden costs.