Free Online Calculators
Do the math in seconds — mortgage payments, loan costs, body metrics, percentages, dates, grades, and more. Every tool is free, instant, and works great on your phone.
Popular Calculators
Mortgage Calculator
Free mortgage calculator estimates your monthly payment including principal, interest, property tax, homeowners insurance, PMI, and HOA fees.
Financial
BMI Calculator
Free BMI calculator using imperial or metric units.
Fitness & Health
Percentage Calculator
Free percentage calculator handles the three most common questions: what is X% of Y, X is what percent of Y, and percent increase or decrease between two numbers.
Math
Calorie Calculator
Find out how many calories you need per day to maintain, lose, or gain weight.
Fitness & Health
Loan Calculator
Calculate monthly payments and total interest for any personal, auto, or student loan.
Financial
Age Calculator
Find your exact age in years, months, and days, plus a countdown to your next birthday.
Other
Compound Interest Calculator
See how compound interest grows your savings and investments.
Financial
GPA Calculator
Calculate your grade point average on the standard US 4.
Other
Sales Tax Calculator
Add sales tax to a pre-tax price or remove it from a tax-included receipt.
Financial
Date Calculator
Free date calculator: add or subtract years, months, weeks, and days from any date, or count the days and business days between two dates.
Other
Browse by Category
Financial Calculators
Mortgage, loan, and investment calculators that help you plan major money decisions with confidence.
- Mortgage Calculator
- Loan Calculator
- Compound Interest Calculator
- Sales Tax Calculator
- Auto Loan Calculator
- Interest Calculator
- Payment Calculator
- Amortization Calculator
- Investment Calculator
- Currency Calculator
- Inflation Calculator
- Retirement Calculator
- Finance Calculator
- Mortgage Payoff Calculator
- Income Tax Calculator
- Salary Calculator
- 401k Calculator
- Interest Rate Calculator
- House Affordability Calculator
- Savings Calculator
- Rent Calculator
- Marriage Tax Calculator
- Estate Tax Calculator
- Social Security Calculator
- Annuity Calculator
- Annuity Payout Calculator
- Credit Card Calculator
- Credit Cards Payoff Calculator
- Debt Payoff Calculator
- Debt Consolidation Calculator
- Repayment Calculator
- Student Loan Calculator
- College Cost Calculator
- Simple Interest Calculator
- CD Calculator
- Bond Calculator
- Mutual Fund Calculator
- Roth IRA Calculator
- Traditional IRA Calculator
- RMD Calculator
- VAT Calculator
- Cash Back or Low Interest Calculator
- Auto Lease Calculator
- Depreciation Calculator
- Average Return Calculator
- Margin Calculator
- Discount Calculator
- Business Loan Calculator
- Debt-to-Income Ratio Calculator
- Real Estate Calculator
- Take-Home-Paycheck Calculator
- Personal Loan Calculator
- Boat Loan Calculator
- Lease Calculator
- Refinance Calculator
- Budget Calculator
- Rental Property Calculator
- IRR Calculator
- ROI Calculator
- APR Calculator
- FHA Loan Calculator
- VA Mortgage Calculator
- Home Equity Loan Calculator
- HELOC Calculator
- Down Payment Calculator
- Rent vs. Buy Calculator
- Payback Period Calculator
- Present Value Calculator
- Future Value Calculator
- Commission Calculator
- Mortgage Calculator UK
- Canadian Mortgage Calculator
- Mortgage Amortization Calculator
- Percent Off Calculator
- Pension Calculator
Fitness & Health Calculators
Evidence-based body metrics and nutrition targets so you can track progress toward a healthier you.
- BMI Calculator
- Calorie Calculator
- Body Fat Calculator
- BMR Calculator
- Macro Calculator
- Ideal Weight Calculator
- Pregnancy Calculator
- Pregnancy Weight Gain Calculator
- Pregnancy Conception Calculator
- Due Date Calculator
- Pace Calculator
- Army Body Fat Calculator
- Carbohydrate Calculator
- Lean Body Mass Calculator
- Healthy Weight Calculator
- Calories Burned Calculator
- One Rep Max Calculator
- Target Heart Rate Calculator
- Protein Calculator
- Fat Intake Calculator
- TDEE Calculator
- Ovulation Calculator
- Conception Calculator
- Period Calculator
- GFR Calculator
- Body Type Calculator
- Body Surface Area Calculator
- BAC Calculator
- Anorexic BMI Calculator
- Weight Watchers Points Calculator
- Overweight Calculator
Math Calculators
Everyday math helpers, from percentages to statistics, with instant answers and clear explanations.
- Percentage Calculator
- Scientific Calculator
- Basic Calculator
- Fraction Calculator
- Matrix Calculator
- Big Number Calculator
- Binary Calculator
- Hex Calculator
- Long Division Calculator
- Triangle Calculator
- Volume Calculator
- Standard Deviation Calculator
- Random Number Generator
- Number Sequence Calculator
- Percent Error Calculator
- Exponent Calculator
- Half-Life Calculator
- Quadratic Formula Calculator
- Slope Calculator
- Log Calculator
- Area Calculator
- Sample Size Calculator
- Probability Calculator
- Statistics Calculator
- Mean, Median, Mode, Range Calculator
- Permutation and Combination Calculator
- Z-score Calculator
- Confidence Interval Calculator
- Ratio Calculator
- Distance Calculator
- Circle Calculator
- Surface Area Calculator
- Pythagorean Theorem Calculator
- Right Triangle Calculator
- Root Calculator
- LCM Calculator
- Greatest Common Factor Calculator
- Factor Calculator
- Rounding Calculator
- Scientific Notation Calculator
- Prime Factorization Calculator
- Common Factor Calculator
- Average Calculator
- P-value Calculator
Other Calculators
Practical calculators for dates, school, shopping, and daily life in the United States.
- Age Calculator
- Date Calculator
- GPA Calculator
- Time Calculator
- Hours Calculator
- Grade Calculator
- Height Calculator
- Concrete Calculator
- IP Subnet Calculator
- Bra Size Calculator
- Password Generator
- Dice Roller
- Fuel Cost Calculator
- Voltage Drop Calculator
- BTU Calculator
- Square Footage Calculator
- Time Zone Calculator
- Love Calculator
- GDP Calculator
- Gas Mileage Calculator
- Horsepower Calculator
- Engine Horsepower Calculator
- Stair Calculator
- Resistor Calculator
- Ohms Law Calculator
- Electricity Calculator
- Shoe Size Conversion
- Tip Calculator
- Mileage Calculator
- Density Calculator
- Mass Calculator
- Weight Calculator
- Speed Calculator
- Molarity Calculator
- Molecular Weight Calculator
- Roman Numeral Converter
- Golf Handicap Calculator
- Sleep Calculator
- Tire Size Calculator
- Roofing Calculator
- Tile Calculator
- Mulch Calculator
- Gravel Calculator
- Wind Chill Calculator
- Heat Index Calculator
- Dew Point Calculator
- Bandwidth Calculator
- Base64 Encode / Decode
- URL Encode / Decode
- Time Duration Calculator
- Day Counter
- Day of the Week Calculator
- Time Card Calculator
- Conversion Calculator
Why Online Calculator?
We build every calculator from scratch and test it against real-world scenarios used across the United States — from state sales tax rates to standard 4.0 GPA scales and conventional 30-year mortgages. Results update as you type, nothing is stored on our servers, and no registration is ever required.
Currently offering 204 free calculators, with new tools added regularly.