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Free calculators that show their work

Free calculators and practical tools for money, home, work, health, shopping, writing, and web tasks. See the result, method, and assumptions.

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Percentage CalculatorFind a percent of a number, compare a part with a whole, or calculate percentage change.Mortgage Affordability CalculatorUse this mortgage affordability calculator to estimate how much house you can afford from income, debts, down payment, rate, loan term, property taxes, insurance, HOA, and debt-limit assumptions.BMI CalculatorUse this BMI calculator to estimate body mass index, BMI category, and a healthy BMI weight range from pounds and feet/inches or kilograms and centimeters.Profit Margin CalculatorUse this profit margin calculator to compare revenue, cost of goods, operating expenses, gross profit, net profit, markup, break-even revenue, and revenue for target margin.Word CounterUse this word counter to count words, characters, sentences, paragraphs, and estimated reading time for any text.QR Code GeneratorUse this QR code generator to create a scannable code for links, WiFi access, contact details, coupons, menus, signs, flyers, and handoffs without uploading the payload.
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Find the tool that matches the question.

Browse money, health, home projects, work, writing, and everyday tasks.

Everyday Calculators

Common calculators for percentages, dates, tips, age, time, unit conversions, home projects, and other everyday questions.

Money Calculators

Simple calculators for budget, tax estimates, emergency funds, debt payoff, loans, savings, rent, salary, mortgage affordability, and household money math.

Health Calculators

Quick health and fitness calculators for BMI, calorie estimates, weight ranges, and everyday wellness planning.

Business Tools

Practical tools for rates, invoices, cash flow, cash runway, profit, pricing, and small business planning.

Social Media Tools

Creator tools for TikTok, Instagram, YouTube, engagement, save rates, Shorts RPM, sponsorship pricing, media kits, creator income, and campaign ROI.

Text and Writing Tools

Text tools for word count, characters, case conversion, hashtags, meta descriptions, platform limits, usernames, hooks, headlines, bios, and CTAs.

Utility Tools

Browser-first utilities for QR codes, links, files, formats, web snippets, and other practical tasks that do not need a spreadsheet-style calculator.

Popular calculator tasks

Start from the decision you are trying to make.

Browse a task group when you know the question but not the calculator name.

Shop, split, and compare prices

Fast calculators for discounts, sales tax, tips, unit prices, fuel costs, and percentage checks before you buy.

5 tools
Discount calculatorSale price, savings, and estimated taxUnit price calculatorCompare price per ounce, pound, item, or servingPrice per pound calculatorCompare grocery and bulk packages by cost per poundPrice per ounce calculatorCompare grocery and household packages by cost per ouncePrice per gram calculatorMetric package comparison by gram and per 100g

Measure rooms and home projects

Practical calculators for square footage, paint, tile, concrete, mulch, soil, sod, gravel, fencing, utilities, and appliance energy.

5 tools
Square footage calculatorRoom area, total area, and material cost estimateHome project cost plannerMaterials, labor, fees, contingency, budget, and cost per square footPaint calculatorWall area, gallons needed, and paint costRoom paint calculatorRoom dimensions, wall count, coats, gallons, and costConcrete calculatorCubic yards, 80 lb bags, and material cost

Convert units and recipe measurements

Specific conversion calculators for common searches: inches, pounds, miles, cups, tablespoons, grams, and kitchen measurements.

5 tools
Inches to centimeters calculatorExact inch-to-centimeter conversionPounds to kilograms calculatorWeight conversion for body, luggage, shipping, and gym weightsMiles to kilometers calculatorDistance conversion for driving, races, and mapsCups to tablespoons calculatorUS kitchen conversion for recipesCups to grams calculatorIngredient-aware flour, sugar, butter, oats, rice, and liquid conversions

Plan household money decisions

Budget, paycheck, rent, bill splitting, emergency fund, and savings calculators for household planning.

5 tools
Budget calculatorMonthly income, spending, savings, and surplusSubscription cost calculatorMonthly, annual, and potentially unused recurring spendHousehold supplies budget calculatorPaper, cleaning, laundry, personal care, and other suppliesPaycheck calculatorGross pay, estimated deductions, and take-home payEmergency fund calculatorSavings target and time to reach it

Compare loans and payoff plans

Loan calculators for monthly payments, mortgage planning, refinancing, auto loans, and debt payoff.

5 tools
Mortgage payment calculatorPrincipal, interest, taxes, insurance, and HOAMortgage vs rent calculatorCompare owner net cost with rent cost over a holding periodCar budget calculatorTotal monthly ownership cost compared with your own cap and take-home incomeCar affordability calculatorVehicle price from monthly budget, APR, tax, and feesLoan comparison calculatorCompare monthly payment, total interest, and total cost

Check dates, work hours, and school math

Everyday calculators for date ranges, age, time duration, time cards, grades, GPA, averages, and fractions.

5 tools
Days between dates calculatorCalendar days, weeks, and optional end-date countingBusiness days calculatorWeekdays between dates after holiday or PTO adjustmentsAdd business days calculatorDeadline date after adding workdays and skipping weekendsCountdown calculatorDays, weeks, and approximate months until a target dateTime duration calculatorElapsed time between two clock times
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Guides and workflows

When you need more than a number.

Reusable setups and practical next steps for deeper tasks.

Check a website pageCheck redirects, indexing, previews, headings, images, and links together.Compare work decisionsCompare options, criteria, costs, and trade-offs before committing.Use a templateCopy a checklist, spreadsheet layout, or reusable decision framework.Read a practical guideFollow a worked example or a step-by-step tool workflow.
Individual website checks
Website page QA checklistRedirect Chain CheckerHTTP Headers + Cache CheckerCanonical URL + Meta Robots CheckerRobots.txt + Sitemap CheckerOpen Graph + Twitter Card CheckerJSON-LD Structured Data CheckerHeading Structure + H1 CheckerImage Alt Text CheckerPage Links + Anchor Text Checker