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Popular Calculators
View all →Currency Converter
Convert 42 currencies with live exchange rates — USD, EUR, BRL, and more.
Live ratesCompound Interest Calculator
Calculate compound interest and investment growth. See how your money grows over...
PopularRetirement Calculator
Free retirement calculator. See how much your savings will grow by retirement an...
Popular401(k) Calculator
Free 401(k) calculator. See how your contributions, employer match, salary growt...
PopularRoth IRA Calculator
Free Roth IRA calculator. Project your tax-free retirement balance from annual c...
PopularMortgage Calculator
Free mortgage calculator. Calculate monthly payments, total interest, and amorti...
PopularHome Affordability Calculator
Free home affordability calculator using the 28/36 rule. See how much house you ...
PopularMortgage Refinance Calculator
Free mortgage refinance calculator. See your new monthly payment, how much you s...
PopularBiweekly Mortgage Calculator
Free biweekly mortgage calculator. See how paying half your mortgage every two w...
PopularRent vs Buy Calculator
Free rent vs buy calculator. Compare the monthly and long-term cost of renting v...
PopularLoan Calculator
Free loan calculator. Calculate monthly payments, total interest, and total cost...
PopularAuto Loan Calculator
Free auto loan calculator. Estimate your monthly car payment, total interest, an...
PopularAmortization Calculator
Free amortization calculator with a full year-by-year schedule. See your monthly...
PopularDebt Payoff Calculator
Free debt payoff calculator. Find out how long it will take to pay off your cred...
PopularSalary Calculator
Free salary calculator. Convert hourly wage to annual, monthly, weekly, or daily...
PopularTake-Home Pay Calculator
Free take-home pay calculator for 2026. See your net paycheck after federal inco...
PopularIncome Tax Calculator
Free income tax calculator. Estimate your US federal income tax, after-tax incom...
PopularCapital Gains Tax Calculator
Free 2026 capital gains tax calculator. Estimate federal tax on stocks, crypto, ...
PopularSales Tax Calculator
Free sales tax calculator. Add sales tax to a price or remove tax from a total. ...
PopularPercentage Calculator
Free percentage calculator. Calculate percent of a number, percentage change, in...
PopularDiscount Calculator
Free discount calculator. Find the sale price and how much you save on any perce...
PopularBMI Calculator
Calculate your BMI (Body Mass Index) instantly. Supports metric and imperial uni...
PopularCalorie Calculator
Free calorie calculator. Find your daily calorie needs to maintain, lose, or gai...
PopularSleep Calculator
Free sleep calculator. Find the best time to go to bed or wake up based on 90-mi...
PopularPregnancy Due Date Calculator
Free pregnancy due date calculator. Find your estimated due date, conception dat...
PopularRunning Pace Calculator
Free running pace calculator. Find your pace per km and mile, plus speed, from y...
PopularAge Calculator
Free age calculator. Find your exact age in years, months, and days. Calculate a...
PopularDate Difference Calculator
Calculate the number of days, weeks, months, and business days between two dates...
PopularHours Calculator
Free hours calculator. Calculate hours and minutes worked between a start and en...
Popularkg to lbs Converter
Convert kilograms to pounds instantly. Free kg to lbs converter with stone and o...
Popularcm to inches Converter
Convert centimeters to inches instantly. Free cm to inches converter with feet a...
PopularCelsius to Fahrenheit Converter
Convert Celsius to Fahrenheit instantly. Free temperature converter. Formula: °F...
PopularCooking Measurement Converter
Free cooking converter. Convert cups, tablespoons, and teaspoons to grams, ounce...
PopularSquare Footage Calculator
Free square footage calculator. Calculate area in square feet and square meters ...
PopularROI Calculator
Free ROI calculator. Calculate return on investment, net profit, and annualized ...
PopularFreelance Rate Calculator
Free freelance rate calculator. Find the hourly rate you need to charge to hit y...
PopularAI / LLM Cost Calculator
Free AI cost calculator. Estimate your monthly LLM API costs based on token usag...
PopularGPA Calculator
Free GPA calculator. Calculate your grade point average on the 4.0 scale using y...
PopularWord Counter
Free online word counter and character counter. Instantly count words, character...
PopularPassword Generator
Free strong password generator. Create secure, random passwords with custom leng...
PopularRandom Number Generator
Free random number generator. Pick one or many random numbers in any range, with...
PopularBrowse by Category
Finance
Compound interest, ROI, savings, investment calculators
Loan
Loan payment, amortization, debt payoff calculators
Mortgage
Mortgage payment, refinance, affordability calculators
Salary & Pay
Salary, hourly rate, paycheck, raise calculators
Tax
Income tax, sales tax, capital gains calculators
Percentage
Percentage, discount, increase, tip calculators
Health
BMI, calorie, body fat, water intake calculators
Fitness
Workout, running pace, one rep max calculators
Date & Time
Age, date difference, business days calculators
Unit Converter
Length, weight, temperature, volume converters
Currency
Currency conversion and exchange rate tools
Math
Scientific, algebra, geometry, statistics calculators
Construction
Area, volume, concrete, flooring calculators
Business
Profit margin, break-even, markup calculators
AI Cost
LLM token cost, API usage, AI budget calculators
Education
GPA, grade, student loan calculators
Utility Tools
Word counter, password generator, random number, and handy everyday tools
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Available in English, Spanish, German, French, and Portuguese, with more languages being added over time.