Percentage calculator
Calculate percentages online, including percent of a number, percentage increase, and percentage decrease.
Free web browser tools
Calculator
Enter your values and get an immediate result with the relevant totals, estimates, or breakdowns.
Age calculator
Calculate exact age from date of birth in years, months, days, and more with a simple online age calculator.
BMI calculator
Calculate your BMI online using height and weight. Get body mass index results with metric and imperial units.
Mortgage calculator
Estimate monthly mortgage payments with loan amount, interest rate, term, deposit, taxes, and fees.
Loan calculator
Calculate loan payments, total interest, and repayment schedules for personal loans and other borrowing.
Tip calculator
Calculate tips and split bills online. Enter bill amount, tip percentage, and number of people.
Date / days-between calculator
Calculate the absolute number of calendar days between two dates online, with equivalent weeks and approximate months.
Compound interest calculator
Calculate compound interest, investment growth, deposits, and future value with an easy online calculator.
Hours / time calculator
Calculate hours and minutes, add or subtract time, and find time between two times online.
Scientific calculator
Use a free online scientific calculator for advanced math, trigonometry, exponents, roots, and more.
Calorie calculator
Estimate daily calorie needs based on age, height, weight, activity level, and goals.
Due date / pregnancy calculator
Estimate a pregnancy due date from the first day of your last menstrual period and see the estimated current gestational age. Uses the standard 280-day calculation.
GPA calculator
Calculate a credit-weighted GPA online from course grades and credit hours using a standard 4.0 scale. Add or remove courses and see total credits instantly.
Salary / paycheck calculator
Estimate take-home pay from salary, tax, deductions, and pay frequency with an online paycheck calculator.
Sales tax / VAT calculator
Calculate sales tax or VAT online. Add tax to a price or work backwards from a tax-inclusive total.
Fraction calculator
Calculate fractions online. Add, subtract, multiply, divide, simplify, and convert fractions easily.
Square footage calculator
Calculate square footage and area online for rooms, walls, floors, and other spaces.
Discount calculator
Calculate discounts, sale prices, savings, and final price after a percentage off.
Percentage increase/decrease
Calculate percentage increase, percentage decrease, and percent change between two numbers.
Grade / test score calculator
Calculate test grades, percentages, and final scores from points earned and total points possible.
Profit margin calculator
Calculate profit margin, markup, and gross profit from cost and selling price, or find the price needed to hit a target margin.
Retirement calculator
See how much you'll have at retirement, what income it can pay, and how much to save each month to hit your goal — adjusted for inflation.
401(k) calculator
Project your 401(k) balance at retirement with employer match, salary raises, and 2026 IRS contribution limits. Year-by-year growth table.
Salary to hourly calculator
Convert an annual salary to an hourly wage, plus daily, weekly, biweekly, and monthly pay. Adjust hours per week and paid weeks.
Hourly to salary calculator
Turn an hourly wage into annual salary, monthly, biweekly, and weekly pay. Includes overtime hours and unpaid time off.
Income tax calculator
Estimate 2026 US federal income tax and FICA, or UK 2026/27 income tax and National Insurance. See take-home pay and tax brackets.
Car loan calculator
Work out your monthly car payment with down payment, trade-in, sales tax, and fees. See total interest and a yearly payoff table.
House affordability calculator
How much house can I afford? Find your maximum home price from income, debts, down payment, rate, taxes, insurance, and lender ratios.
Amortization schedule calculator
Build a full loan amortization schedule by month or year. See principal vs interest, payoff date, and savings from extra payments.
Debt payoff calculator
Plan how to pay off multiple debts with the snowball or avalanche method. See your debt-free date, payoff order, and interest saved.
Credit card payoff calculator
Find how long it takes to pay off a credit card, or the monthly payment needed to be debt-free by a date. Shows total interest.
Inflation calculator
See what money from any year is worth today using official US CPI (from 1913) and UK price data (from 1800), or a custom inflation rate.
ROI calculator
Calculate return on investment, net profit, and annualized ROI (CAGR) from what you invested and what you got back.
Break-even calculator
Find the break-even point in units and revenue from fixed costs, price, and variable cost. Includes target profit and margin of safety.
Markup calculator
Calculate selling price from cost and markup, markup from cost and price, or cost from price. Shows gross margin alongside markup.
Overtime calculator
Calculate overtime pay at time and a half or any multiplier, plus double time. See total pay, overtime rate, and yearly earnings.
TDEE calculator
Calculate your TDEE and BMR to find maintenance calories, plus targets to lose or gain weight. Mifflin-St Jeor or Katch-McArdle.
Body fat calculator
Estimate body fat percentage with the U.S. Navy tape-measure method. See fat mass, lean mass, BMI, and your fitness category.
Pace calculator
Calculate running pace, finish time, or distance in km or miles. Get race predictions for 5K, 10K, half marathon, and marathon plus splits.
Mean, median, mode calculator
Find the mean, median, mode, and range of a list of numbers, plus quartiles, sum, and count. Paste numbers separated by commas or lines.
Standard deviation calculator
Calculate sample or population standard deviation and variance with step-by-step deviations, z-scores, and standard error.
Date calculator
Add or subtract days, weeks, months, or years from a date. Shows the weekday, day of year, and week number of the result.
Business days calculator
Count working days between two dates or add business days to a date, skipping weekends and US federal or UK bank holidays.
Decimal to fraction converter
Convert decimals to simplified fractions and mixed numbers, including repeating decimals, or turn a fraction into a decimal.
Calculator FAQs
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Tags group tools by shared traits such as file converter, in browser, or privacy friendly so you can filter the directory by feature.