Free Calculators
The calculators people search for daily — BMI, loan, mortgage, percentage, tip, GPA, calorie, sleep, and more.
BMI Calculator
Calculate your Body Mass Index (BMI).
Loan Calculator
Estimate monthly loan payments and interest.
Mortgage Calculator
Estimate your monthly mortgage payment.
Compound Interest Calculator
See how your savings grow over time.
Tip Calculator
Calculate the tip and split the bill.
Salary Calculator
Convert hourly pay to annual salary.
GPA Calculator
Calculate your GPA from grades and credits.
Calorie Calculator
Estimate your daily calorie needs (TDEE).
Sleep Calculator
Find the best bedtime or wake-up time by sleep cycles.
Pregnancy Due Date Calculator
Estimate your due date from your last period.
Final Grade Calculator
Find the score you need on your final exam.
Ovulation Calculator
Estimate your fertile window and ovulation day.
Scientific Calculator
A full scientific calculator in your browser.
Average Calculator
Find the mean, median, mode, and range of any numbers.
Fraction Calculator
Add, subtract, multiply, and divide fractions.
Ratio Calculator
Solve proportions and simplify ratios.
Body Fat Calculator
Estimate your body fat percentage from measurements.
Macro Calculator
Split your daily calories into protein, carbs, and fat.
Pace Calculator
Calculate your running pace and speed.
Concrete Calculator
Estimate concrete for a slab or pad.
Square Footage Calculator
Calculate area in square feet.
Tile Calculator
Estimate how many tiles you need.
Roofing Calculator
Estimate roof area and squares.
Mulch Calculator
Estimate mulch for a garden bed.
Gravel Calculator
Estimate gravel by volume and weight.
Stair Calculator
Calculate steps and riser height.
BTU Calculator
Estimate the BTU capacity a room needs.
Height Calculator
Predict a child's adult height.
Density Calculator
Calculate density from mass and volume.
Mass Calculator
Calculate mass from density and volume.
Molarity Calculator
Calculate solution molarity.
GDP Calculator
Calculate GDP from its components.
Fuel Cost Calculator
Estimate the fuel cost of a trip.
Gas Mileage Calculator
Calculate your vehicle's fuel economy.
Mileage Calculator
Calculate mileage reimbursement.
Horsepower Calculator
Calculate horsepower from torque and RPM.
Engine Horsepower Calculator
Estimate horsepower from the quarter mile.
Tire Size Calculator
Find a tire's diameter and circumference.
Wind Chill Calculator
Calculate the wind chill temperature.
Heat Index Calculator
Calculate the heat index (feels-like).
Dew Point Calculator
Calculate the dew point.
Shoe Size Calculator
Estimate shoe size from foot length.
Bra Size Calculator
Estimate bra band and cup size.
Golf Handicap Calculator
Calculate a golf handicap differential.
Molecular Weight Calculator
Find the molar mass of a chemical formula.
Grade Calculator
Calculate your weighted class grade.
Speed Calculator
Solve for speed, distance, or time.
About these calculators
A collection of free online calculators for the numbers that come up in everyday life — BMI, calorie and TDEE, loan and mortgage payments, compound interest, percentage, tip and bill splitting, sales tax, GPA and final grade, salary, sleep cycles, pregnancy due date, and more. Each one is instant, mobile-friendly, and needs no sign-up — just enter your numbers and get the answer, with the formula explained so you understand the result.
Frequently asked questions
Are these calculators free to use?
Yes — every calculator is completely free, works in your browser, and requires no account or download.
Do the calculators work on my phone?
Yes — they're fully responsive and work in any modern browser on phones, tablets, and computers.
How accurate are the results?
Each calculator uses the standard, published formula for its task (for example, Mifflin-St Jeor for calories or amortization for loans) and shows the method so you can verify it.