Free Online Calculators
500+ calculators for finance, health, math, fitness, construction, and more. Instant results, no sign-up required.
Math Calculators
Percentage Calculator
% of a number, increase, decrease
Fraction Calculator
Add, subtract, multiply, divide fractions
Scientific Calculator
Advanced math operations
Square Root Calculator
Find square roots instantly
Random Number Generator
Generate random numbers
GPA Calculator
Calculate your grade point average
Exponent Calculator
Powers and exponents
Logarithm Calculator
Log and natural log
LCM Calculator
Least common multiple
GCF Calculator
Greatest common factor
Financial Calculators
Mortgage Calculator
Monthly payment, amortization schedule
Loan Calculator
Loan payments, interest, payoff date
Compound Interest Calculator
Grow your savings
Auto Loan Calculator
Car payment estimator
Salary Calculator
Hourly, weekly, monthly, annual
Investment Calculator
Future value of investments
Savings Calculator
Savings growth over time
Retirement Calculator
Plan for retirement
Inflation Calculator
Purchasing power over time
Currency Converter
Exchange rates calculator
Health Calculators
BMI Calculator
Body Mass Index
Calorie Calculator
Daily calorie needs
Body Fat Calculator
Estimate body fat %
BMR Calculator
Basal metabolic rate
TDEE Calculator
Total daily energy expenditure
Pregnancy Calculator
Due date & milestones
Ovulation Calculator
Fertility window
Ideal Weight Calculator
Healthy weight range
Macro Calculator
Protein, carbs, fat
Water Intake Calculator
Daily water needs
Date & Time Calculators
Fitness & Sports
Construction & Home
Tax & Salary
Conversion & Other
Why HQ Calculator?
Built for speed, accuracy, and simplicity.
Instant Results
No loading, no submit button. Results update as you type. Every calculator loads in under 1 second.
No Sign-Up Ever
100% free, no registration, no email walls. Just open and calculate. Share results with a simple link.
Verified Accuracy
Every formula is verified against official sources. Financial calculators reviewed by professionals.