Calculators
Calculators for money, health, school, home projects and everyday maths, plus converters between metric and US/imperial units. Each page shows the formula it uses, so you can check the working.
Results are estimates for planning — not financial, medical or professional advice.
Money & finance
Mortgage Calculator
Estimate your monthly mortgage payment, interest and payoff timeline.
Loan Calculator
Calculate the monthly payment for any fixed-rate loan.
APR Calculator
Find the APR of a loan once up-front fees are included.
Credit Card Payoff Calculator
See how long it takes to pay off a credit card and how much interest you'll pay.
Debt Payoff Calculator
Compare the avalanche and snowball methods for paying off several debts.
Debt-to-Income Ratio Calculator
Calculate your DTI ratio from income and monthly debt payments.
Compound Interest Calculator
See how an investment grows with compound interest over time.
Savings Calculator
See how regular contributions and interest grow your savings.
Simple Interest Calculator
Calculate interest earned on a principal at a fixed rate.
ROI Calculator
Work out return on investment, with an annualized rate when you add a time period.
Break-Even Calculator
Find how many units you need to sell to cover your costs.
Salary Calculator
Convert gross pay between hourly, daily, weekly, biweekly, monthly and annual.
Profit Margin Calculator
Calculate profit, margin percentage and markup from cost and price.
Markup Calculator
Set a selling price from cost and your target markup percentage.
VAT Calculator
Add or remove VAT at any rate — net, VAT amount and gross.
Sales Tax Calculator
Calculate sales tax and the final price at any custom rate.
Discount Calculator
Calculate the final price after one or two discounts.
Tip Calculator
Calculate tip amount and split the bill per person.
Marketing & e-commerce
CPM Calculator
Work out cost per 1,000 impressions, total ad cost or impressions.
CPC Calculator
Find cost per click from ad spend and clicks — plus CTR if you add impressions.
ROAS Calculator
Calculate return on ad spend as a ratio and a percentage.
Conversion Rate Calculator
Work out the percentage of visitors, clicks or leads that convert.
Average Order Value Calculator
Divide total revenue by orders to get your average order value (AOV).
Health & fitness
BMI Calculator
Calculate your Body Mass Index from height and weight.
Calorie Calculator
Estimate the calories you need to maintain your weight.
BMR Calculator
Estimate your Basal Metabolic Rate — calories burned at rest.
TDEE Calculator
See your estimated calorie burn at every activity level.
Macro Calculator
Get estimated protein, carb and fat targets for your goal.
Body Fat Calculator
Estimate body fat percentage from tape-measure readings (U.S. Navy method).
Ideal Weight Calculator
See estimated ideal weight from four established formulas.
Protein Calculator
Estimate a daily protein range from your body weight and activity.
Water Intake Calculator
Estimate your daily water intake from weight and activity.
Pace Calculator
Work out running pace, finish time or distance in kilometres and miles.
Steps to Miles Converter
Convert a step count into miles using your height or step length.
Steps to KM Converter
Convert a step count into kilometres using your height or step length.
Cars & driving
Car Loan Calculator
Estimate your monthly car payment, including trade-in and tax.
Car Depreciation Calculator
Estimate a car's future value from its price and depreciation rates.
Fuel Cost Calculator
Estimate fuel needed and the cost of a trip from distance, economy and price.
MPG Calculator
Work out your car's fuel economy in MPG, km/L and L/100 km.
MPG to L/100 km Converter
Convert US or UK miles per gallon to litres per 100 km.
L/100 km to MPG Converter
Convert litres per 100 km to US and UK miles per gallon.
Math & statistics
Percentage Calculator
Calculate percentages, increases and decreases.
Scientific Calculator
A scientific calculator with trig, logs, powers and roots.
Fraction Calculator
Add, subtract, multiply and divide fractions with exact simplified answers.
Probability Calculator
Calculate the probability of A, not A, A and B, or A or B.
Standard Deviation Calculator
Find the mean, variance and standard deviation of a list of numbers.
Triangle Calculator
Solve a triangle's missing sides and angles, plus its area and perimeter.
Aspect Ratio Calculator
Simplify a ratio or calculate a missing width or height.
Date & time
Age Calculator
Calculate exact age in years, months and days.
Date Difference Calculator
Find the exact time between two dates.
Business Days Calculator
Count business days between two dates, excluding weekends.
Time Calculator
Add or subtract hours, minutes and seconds, or find the time between two times.
Hours Calculator
Calculate hours worked between a start and end time.
Home & construction
Square Footage Calculator
Work out the area of rooms and spaces in square feet and square metres.
Paint Calculator
Estimate how much paint you need for a room's walls and ceiling.
Concrete Calculator
Estimate concrete for slabs, patios, footings and posts in yards, m³ or bags.
Tile Calculator
Work out how many tiles you need for a floor or wall, including waste.
Flooring Calculator
Estimate flooring for one or more rooms, with waste and box count.
Roofing Calculator
Estimate roof area, roofing squares and shingle bundles from pitch.
Gravel Calculator
Work out how much gravel you need in cubic yards, cubic metres and tons.
Cubic Yard Calculator
Convert length, width and depth into cubic yards, feet and metres.
Board Foot Calculator
Calculate board feet for lumber from thickness, width and length.
School & grades
Unit conversions
Unit Converter
Convert length, weight, temperature, area, volume and speed.
File Size Converter
Convert bytes, KB, MB, GB and TB — in decimal or binary (KiB, MiB, GiB).
CM to Inches Converter
Convert centimeters to inches instantly.
Inches to CM Converter
Convert inches to centimeters instantly.
MM to Inches Converter
Convert millimeters to inches instantly.
Inches to MM Converter
Convert inches to millimeters instantly.
Feet to Inches Converter
Convert feet to inches instantly.
Inches to Feet Converter
Convert inches to feet instantly.
Miles to KM Converter
Convert miles to kilometers instantly.
KM to Miles Converter
Convert kilometers to miles instantly.
Grams to Ounces Converter
Convert grams to ounces instantly.
Ounces to Grams Converter
Convert ounces to grams instantly.
KG to LBS Converter
Convert kilograms to pounds instantly.
LBS to KG Converter
Convert pounds to kilograms instantly.
Celsius to Fahrenheit Converter
Convert Celsius to Fahrenheit instantly.
Fahrenheit to Celsius Converter
Convert Fahrenheit to Celsius instantly.
Meters to Feet Converter
Convert meters to feet instantly.
Feet to Meters Converter
Convert feet to meters instantly.
Liters to Gallons Converter
Convert litres to US or UK (imperial) gallons.
Gallons to Liters Converter
Convert US or UK (imperial) gallons to litres.
MPH to KM/H Converter
Convert miles per hour to kilometres per hour.
KM/H to MPH Converter
Convert kilometres per hour to miles per hour.
Stone to KG Converter
Convert stones and pounds to kilograms.
KG to Stone Converter
Convert kilograms to stones and pounds.