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Most wanted calculators

Selected for everyday usefulness.

001 / Math

Percentage Calculator

Calculate percentages, percent change, and reverse percentages instantly with this free online tool.

002 / Date & Time

Age Calculator

Find your exact age in years, months, days, hours, and minutes from your date of birth.

003 / Date & Time

Date Difference Calculator

Calculate the exact number of days, weeks, months, and years between two dates.

004 / Date & Time

Hours Calculator

Add up hours and minutes between two times, perfect for timesheets, payroll, and scheduling.

005 / Education

Test Score Calculator

Enter questions right or wrong to instantly see your test grade as a percentage and letter grade.

006 / Pay & Taxes

Salary to Hourly Calculator

Convert your annual salary to an hourly wage based on your work hours per week.

007 / Business & Ecommerce

Profit Margin Calculator

Calculate gross profit margin, markup, and profit from cost and revenue.

008 / Math

Fraction Calculator

Add, subtract, multiply, and divide fractions with step-by-step simplified results.

009 / Home & Construction

Concrete Calculator

Estimate cubic yards, bags, and cost of concrete for slabs, footings, columns, and stairs.

010 / Home & Construction

Cubic Yard Calculator

Convert project dimensions into cubic yards for concrete, soil, gravel, and mulch orders.

011 / Home & Construction

Roof Pitch Calculator

Find roof pitch, angle, and slope from rise and run — or convert between pitch formats.

012 / Home & Construction

Gravel Calculator

Estimate tons and cubic yards of gravel needed for driveways, paths, and landscaping.

013 / Home & Construction

Mulch Calculator

Calculate bags or cubic yards of mulch needed for garden beds by area and depth.

014 / Home & Construction

Board Foot Calculator

Calculate board feet and lumber cost from thickness, width, length, and quantity.

015 / Home & Construction

Deck Material Calculator

Estimate decking boards, joists, screws, and cost for your deck project.

016 / Home & Construction

Paint Calculator

Find out how many gallons of paint you need based on room size, coats, and coverage.

017 / Business & Ecommerce

Markup Calculator

Calculate selling price, markup percentage, and profit from cost.

018 / Pay & Taxes

Tip Calculator

Calculate the tip and split the bill between any number of people.

019 / Automotive & Travel

Fuel Cost Calculator

Estimate the fuel cost of any trip from distance, fuel economy, and gas price.

020 / Education

GPA Calculator

Calculate your GPA from letter grades and credit hours, weighted or unweighted.

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All 135 calculators

001 / Math

Percentage Calculator

Calculate percentages, percent change, and reverse percentages instantly with this free online tool.

002 / Date & Time

Age Calculator

Find your exact age in years, months, days, hours, and minutes from your date of birth.

003 / Date & Time

Date Difference Calculator

Calculate the exact number of days, weeks, months, and years between two dates.

004 / Date & Time

Hours Calculator

Add up hours and minutes between two times, perfect for timesheets, payroll, and scheduling.

005 / Education

Test Score Calculator

Enter questions right or wrong to instantly see your test grade as a percentage and letter grade.

006 / Pay & Taxes

Salary to Hourly Calculator

Convert your annual salary to an hourly wage based on your work hours per week.

007 / Business & Ecommerce

Profit Margin Calculator

Calculate gross profit margin, markup, and profit from cost and revenue.

008 / Math

Fraction Calculator

Add, subtract, multiply, and divide fractions with step-by-step simplified results.

009 / Home & Construction

Concrete Calculator

Estimate cubic yards, bags, and cost of concrete for slabs, footings, columns, and stairs.

010 / Home & Construction

Cubic Yard Calculator

Convert project dimensions into cubic yards for concrete, soil, gravel, and mulch orders.

011 / Home & Construction

Roof Pitch Calculator

Find roof pitch, angle, and slope from rise and run — or convert between pitch formats.

012 / Home & Construction

Gravel Calculator

Estimate tons and cubic yards of gravel needed for driveways, paths, and landscaping.

013 / Home & Construction

Mulch Calculator

Calculate bags or cubic yards of mulch needed for garden beds by area and depth.

014 / Home & Construction

Board Foot Calculator

Calculate board feet and lumber cost from thickness, width, length, and quantity.

015 / Home & Construction

Deck Material Calculator

Estimate decking boards, joists, screws, and cost for your deck project.

016 / Home & Construction

Paint Calculator

Find out how many gallons of paint you need based on room size, coats, and coverage.

017 / Business & Ecommerce

Markup Calculator

Calculate selling price, markup percentage, and profit from cost.

018 / Pay & Taxes

Tip Calculator

Calculate the tip and split the bill between any number of people.

019 / Automotive & Travel

Fuel Cost Calculator

Estimate the fuel cost of any trip from distance, fuel economy, and gas price.

020 / Education

GPA Calculator

Calculate your GPA from letter grades and credit hours, weighted or unweighted.

021 / Finance

Mortgage Calculator

Estimate your monthly mortgage payment with taxes, insurance, PMI, and full amortization.

022 / Finance

Loan Calculator

Calculate monthly payments, total interest, and payoff schedule for any loan.

023 / Finance

Compound Interest Calculator

See how your money grows with compound interest, regular contributions, and time.

024 / Finance

Auto Loan Calculator

Estimate monthly car payments including trade-in, down payment, sales tax, and fees.

025 / Finance

Amortization Calculator

Generate a full month-by-month amortization schedule for any loan.

026 / Finance

Retirement Calculator

Project your retirement savings and see if you're on track to retire when you want.

027 / Finance

401(k) Calculator

Project your 401(k) balance at retirement including employer match and salary growth.

028 / Finance

Home Affordability Calculator

Find out how much house you can afford based on income, debts, and down payment.

029 / Finance

Credit Card Payoff Calculator

See how long it takes to pay off credit card debt and how much interest you'll pay.

030 / Finance

Debt Payoff Calculator

Compare snowball vs. avalanche strategies and get a debt-free date for all your debts.

031 / Finance

Investment Return Calculator

Calculate total and annualized return on any investment over time.

032 / Business & Ecommerce

ROI Calculator

Calculate return on investment for any business spend, project, or campaign.

033 / Finance

Savings Calculator

Project how your savings grow over time with regular deposits and interest.

034 / Finance

Refinance Calculator

Compare your current mortgage to a refinance and see monthly and lifetime savings.

035 / Finance

Rent vs. Buy Calculator

Compare the true long-term cost of renting versus buying a home.

036 / Finance

Debt-to-Income Calculator

Calculate your DTI ratio to see how lenders view your borrowing capacity.

037 / Finance

Down Payment Calculator

See how your down payment affects loan amount, PMI, and monthly payment.

038 / Finance

HELOC Calculator

Estimate how much home equity you can borrow against with a HELOC.

039 / Finance

Simple Interest Calculator

Calculate simple interest on loans or deposits with the I = Prt formula.

040 / Finance

Savings Goal Calculator

Find out how much to save each month to hit any savings goal by a target date.

041 / Finance

Personal Loan Calculator

Estimate monthly payments and total interest for a personal loan.

042 / Finance

Car Payment Calculator

Quickly estimate your monthly car payment from price, rate, and term.

043 / Finance

Mortgage Payment Calculator

Simple principal-and-interest monthly mortgage payment estimate.

044 / Finance

CD Calculator

Calculate the return on a certificate of deposit at maturity.

045 / Finance

APY Calculator

Convert an interest rate to APY based on compounding frequency.

046 / Health & Fitness

BMI Calculator

Calculate your Body Mass Index and see where you fall on the BMI scale.

047 / Health & Fitness

Calorie Calculator

Estimate daily calories to maintain, lose, or gain weight based on your stats and activity.

048 / Health & Fitness

TDEE Calculator

Calculate your Total Daily Energy Expenditure from BMR and activity level.

049 / Health & Fitness

BMR Calculator

Find your Basal Metabolic Rate — the calories your body burns at rest.

050 / Health & Fitness

Body Fat Calculator

Estimate body fat percentage using the U.S. Navy circumference method.

051 / Health & Fitness

Macro Calculator

Get daily protein, carb, and fat targets based on your calories and goal.

052 / Health & Fitness

Calorie Deficit Calculator

Find the calorie deficit needed to reach your goal weight by a target date.

053 / Health & Fitness

Ideal Weight Calculator

See your ideal weight range using Devine, Robinson, Miller, and BMI formulas.

054 / Health & Fitness

Protein Calculator

Calculate your daily protein needs based on weight, activity, and goal.

055 / Health & Fitness

Heart Rate Zone Calculator

Find your five heart-rate training zones from your age or max heart rate.

056 / Pay & Taxes

Paycheck Calculator

Estimate your take-home pay after federal and state taxes and deductions.

057 / Pay & Taxes

Salary Calculator

Convert salary between hourly, weekly, monthly, and annual amounts.

058 / Pay & Taxes

Hourly to Salary Calculator

Convert your hourly wage into weekly, monthly, and annual salary.

059 / Pay & Taxes

Income Tax Calculator

Estimate your federal income tax, effective rate, and marginal bracket.

060 / Pay & Taxes

Sales Tax Calculator

Add or back out sales tax from any price by rate or state.

061 / Pay & Taxes

Take-Home Pay Calculator

See your net pay per paycheck after all taxes and withholdings.

062 / Pay & Taxes

Overtime Calculator

Calculate overtime pay at time-and-a-half or custom multipliers.

063 / Pay & Taxes

Time Card Calculator

Add up weekly work hours from daily clock-in/out times, with breaks and overtime.

064 / Pay & Taxes

Commission Calculator

Calculate commission earnings from sales amount and commission rate.

065 / Pay & Taxes

Raise Calculator

See what a raise means in dollars per paycheck, month, and year.

066 / Pay & Taxes

Bonus Tax Calculator

Estimate taxes withheld from a bonus using the flat supplemental rate or aggregate method.

067 / Pay & Taxes

Self-Employment Tax Calculator

Calculate self-employment tax (Social Security + Medicare) and quarterly estimates.

068 / Pay & Taxes

PTO Calculator

Calculate PTO accrual by pay period and project your balance for future dates.

069 / Math

Percentage Increase Calculator

Calculate the percentage increase between two numbers.

070 / Math

Percentage Decrease Calculator

Calculate the percentage decrease between two numbers.

071 / Math

Average Calculator

Find the mean, median, mode, and range of any set of numbers.

072 / Math

Ratio Calculator

Simplify ratios and solve for missing values in equivalent ratios.

073 / Math

Proportion Calculator

Solve proportions and find the missing value in a/b = c/d.

074 / Math

Decimal to Fraction Calculator

Convert any decimal, including repeating decimals, into a simplified fraction.

075 / Math

Fraction to Decimal Calculator

Convert fractions and mixed numbers into decimals.

076 / Math

Pythagorean Theorem Calculator

Solve for any side of a right triangle using a² + b² = c².

077 / Math

Square Footage Calculator

Calculate square footage of rooms and areas in any shape, with cost per square foot.

078 / Math

Area Calculator

Find the area of rectangles, circles, triangles, trapezoids, and more.

079 / Math

Volume Calculator

Calculate the volume of cubes, cylinders, spheres, cones, and boxes.

080 / Math

Scientific Calculator

Full-featured online scientific calculator with trig, log, exponent, and memory functions.

081 / Math

Time Duration Calculator

Add or subtract hours, minutes, and seconds between two times.

082 / Date & Time

Date Calculator

Add or subtract days, weeks, months, or years from any date.

083 / Date & Time

Days Between Dates Calculator

Count the exact number of days between any two dates, with or without weekends.

084 / Date & Time

Business Days Calculator

Calculate business days between dates or add business days to a date, excluding holidays.

085 / Date & Time

Workdays Calculator

Count workdays in a range with custom workweeks and holiday exclusions.

086 / Date & Time

Time Zone Converter

Convert times between any two time zones, with DST handled automatically.

087 / Date & Time

Birthday Calculator

Discover your exact age, day-of-week born, zodiac sign, and days until your next birthday.

088 / Date & Time

Countdown Timer

Count down the days, hours, minutes, and seconds to any date or event.

089 / Date & Time

Weeks Between Dates Calculator

Calculate the number of weeks and months between two dates.

090 / Home & Construction

Flooring Calculator

Estimate flooring material, boxes, and cost including waste factor.

091 / Home & Construction

Tile Calculator

Calculate how many tiles you need for floors or walls, including grout and waste.

092 / Home & Construction

Drywall Calculator

Estimate drywall sheets, mud, tape, and screws for walls and ceilings.

093 / Home & Construction

Insulation Calculator

Calculate insulation needed by area and recommended R-value for your climate zone.

094 / Home & Construction

Stair Calculator

Calculate rise, run, stringer length, and number of steps for stair building.

095 / Home & Construction

HVAC Sizing Calculator

Estimate the BTU/tonnage needed to heat or cool your space.

096 / Home & Construction

Solar Savings Calculator

Estimate solar panel system size, cost, and 25-year savings for your home.

097 / Home & Construction

Electricity Cost Calculator

Calculate the cost to run any appliance by wattage, hours, and electricity rate.

098 / Automotive & Travel

Gas Cost Calculator

Calculate the total gas cost for a trip and cost per passenger.

099 / Automotive & Travel

MPG Calculator

Calculate your car's real fuel economy from miles driven and gallons used.

100 / Automotive & Travel

Trip Cost Calculator

Estimate the full cost of a road trip: fuel, lodging, food, and tolls.

101 / Automotive & Travel

Driving Time Calculator

Estimate driving time from distance and average speed, with break stops.

102 / Automotive & Travel

EV Charging Cost Calculator

Compare the cost of charging an EV at home vs. public chargers vs. gas.

103 / Automotive & Travel

Car Depreciation Calculator

Estimate your car's future value and total depreciation over time.

104 / Automotive & Travel

Lease Calculator

Estimate monthly car lease payments from cap cost, residual, and money factor.

105 / Automotive & Travel

Tire Size Calculator

Compare two tire sizes and see diameter, speedometer, and clearance differences.

106 / Education

Grade Calculator

Calculate your current class grade from weighted assignments, tests, and exams.

107 / Education

Final Grade Calculator

Find out what you need on the final exam to get your target grade.

108 / Education

Weighted Grade Calculator

Calculate a weighted average grade across categories with different weights.

109 / Education

College GPA Calculator

Calculate semester and cumulative college GPA with credit hours.

110 / Education

Student Loan Calculator

Estimate student loan payments and total interest under standard repayment.

111 / Education

Reading Time Calculator

Estimate how long it takes to read any text or word count.

112 / Education

Word Count Calculator

Count words, characters, sentences, and paragraphs in any text.

113 / Education

Study Time Calculator

Plan how many hours to study per week based on credit hours and difficulty.

114 / Business & Ecommerce

Break-Even Calculator

Find the sales volume needed to cover your fixed and variable costs.

115 / Business & Ecommerce

Discount Calculator

Calculate sale prices, discounts, and savings — including stacked discounts.

116 / Business & Ecommerce

ROAS Calculator

Calculate return on ad spend and the break-even ROAS for your margins.

117 / Business & Ecommerce

Conversion Rate Calculator

Calculate conversion rate from visitors and conversions.

118 / Business & Ecommerce

Customer Lifetime Value Calculator

Estimate the total revenue a customer generates over their lifetime.

119 / Business & Ecommerce

CAC Calculator

Calculate customer acquisition cost and your LTV:CAC ratio.

120 / Business & Ecommerce

CPM Calculator

Calculate cost per thousand impressions, or solve for budget or impressions.

121 / Business & Ecommerce

CPC Calculator

Calculate cost per click from ad spend and total clicks.

122 / Business & Ecommerce

CPA Calculator

Calculate cost per acquisition/action from spend and conversions.

123 / Business & Ecommerce

Gross Margin Calculator

Calculate gross margin percentage and gross profit from revenue and COGS.

124 / Business & Ecommerce

Pricing Calculator

Set a product price from cost, target margin, fees, and shipping.

125 / Business & Ecommerce

Sales Commission Calculator

Calculate tiered or flat sales commissions and total rep earnings.

126 / Conversion

Length Converter

Convert between inches, feet, meters, kilometers, miles, and more instantly with precise conversion factors.

127 / Conversion

Weight Converter

Convert between pounds, kilograms, ounces, grams, and stones instantly with precise conversion factors.

128 / Conversion

Temperature Converter

Convert between Fahrenheit, Celsius, and Kelvin.

129 / Conversion

Volume Converter

Convert between gallons, liters, cups, milliliters, and fluid ounces instantly with precise conversion factors.

130 / Conversion

Area Converter

Convert between square feet, square meters, acres, and hectares instantly with precise conversion factors.

131 / Conversion

Speed Converter

Convert between mph, km/h, knots, and meters per second instantly with precise conversion factors.

132 / Conversion

Time Converter

Convert between seconds, minutes, hours, days, and weeks instantly with precise conversion factors.

133 / Conversion

Currency Converter

Convert between world currencies with up-to-date exchange rates.

134 / Conversion

Pressure Converter

Convert between psi, bar, pascal, and atmospheres instantly with precise conversion factors.

135 / Conversion

Energy Converter

Convert between joules, calories, kWh, and BTU instantly with precise conversion factors.

Good to know

Quick answers about our answers

Are these calculators free?

Yes. Every calculator is free to use with no account required.

Do calculations leave my device?

No. Inputs are processed locally in your browser.

How should I use financial or health results?

Treat them as informational estimates and consult a qualified professional when a decision carries risk.