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Free online calculatorsfor everyday answers.
Plan a project, check your numbers, or solve a problem. Find free calculators for math, money, health, time, and everyday life in one place.
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Useful tools for the questions that come up every day.
- Age CalculatorAge Calculator calculates age between dates or times for deadlines, schedules, milestones, and planning.
- GPA CalculatorTrack courses across semesters, apply weighted grades for Honors or AP classes, and see your cumulative GPA update in real time.
- Markup CalculatorConvert between markup percentage, margin, cost, and selling price to price jobs and products with clear profit visibility.
- Paint CalculatorEstimate interior wall paint from room dimensions or gross wall area, doors, windows, coats, coverage, and optional waste—with optional cost per US gallon or liter.
- Percentage CalculatorFind a percentage of a number, what percent one value is of another, or percentage change between two values—instantly as you type.
- Concrete CalculatorCalculate concrete for slabs, footings, and round columns in cubic yards, cubic feet, or cubic meters. Estimate 40–80 lb bags plus optional safety allowance.
- Date Difference CalculatorDate Difference Calculator calculates date difference between dates or times for deadlines, schedules, milestones, and planning.
- Fraction CalculatorFraction Calculator solves fraction problems with established formulas—enter your values and review precise results for study or design work.
What are you working on?
A few helpful tools for the task in front of you.
Plan a home project
Make sense of your money
Study with confidence
Simplify everyday life
Categories
11 categoriesFrom a quick conversion to your next big project, start with a topic.
- Home & Construction Calculators36 calculatorsBrowse free home and construction calculators online.
- Contractor & Business Calculators10 calculatorsBrowse free contractor and business calculators online.
- Time & Date Calculators18 calculatorsBrowse free time and date calculators online.
- Measurement & Conversion Tools22 calculatorsBrowse free measurement and conversion tools online.
- Math & Geometry Calculators31 calculatorsBrowse free math and geometry calculators online.
- Student & Grade Calculators12 calculatorsBrowse free student and grade calculators online.
- Text Utilities18 calculatorsBrowse free text utility tools online.
- Garden & Landscaping Calculators8 calculatorsBrowse free garden and landscaping calculators online.
- Health & Body Calculators3 calculatorsBrowse free health and body calculators online.
- Finance Calculators7 calculatorsBrowse free finance calculators online.
- Everyday Life Calculators2 calculatorsBrowse free everyday life calculators online.
From question to answer in three steps
- 1
Find your tool
Search by name or explore a category to find a calculator for your task.
- 2
Enter your values
Choose the units and add your numbers. Change an input to compare scenarios.
- 3
Understand the result
Review the result alongside the formula, assumptions, and examples on the calculator page.
All calculators
167 of 167 tools
Explore the full collection. Open a category to see every tool, or use search to narrow your options.
Home & Construction Calculators
36
View category
- Paint Calculator
- Concrete Calculator
- Tile Calculator
- Drywall Calculator
- Roofing Calculator
- Lumber Calculator
- Deck Calculator
- Fence Calculator
- Brick Calculator
- Carpet Calculator
- Hardwood Flooring Calculator
- Insulation Calculator
- Gravel Calculator
- Mulch Calculator
- Sod Calculator
- Wallpaper Calculator
- Vinyl Siding Calculator
- Gutter Calculator
- Stair Calculator
- Baseboard Calculator
- Ceiling Tile Calculator
- Asphalt Calculator
- Rebar Calculator
- Mortar Calculator
- Patio Calculator
- Driveway Calculator
- Rafter Calculator
- Stud Wall Calculator
- Retaining Wall Calculator
- Flooring Underlayment Calculator
- Sand Calculator
- Stone Calculator
- Paver Calculator
- Roof Pitch Calculator
- Pool Volume Calculator
- Soil Calculator
Contractor & Business Calculators
10
Time & Date Calculators
18
View category
- Age Calculator
- Date Difference Calculator
- Days Between Dates Calculator
- Business Days Calculator
- Weeks Between Dates Calculator
- Months Between Dates Calculator
- Add Days Calculator
- Subtract Days Calculator
- Countdown Calculator
- Deadline Calculator
- Work Hours Calculator
- Time Duration Calculator
- Time Zone Converter
- Day of Week Calculator
- Leap Year Calculator
- Due Date Calculator
- Anniversary Calculator
- Retirement Date Calculator
Measurement & Conversion Tools
22
View category
- Length Converter
- Area Converter
- Volume Converter
- Weight Converter
- Temperature Converter
- Speed Converter
- Pressure Converter
- Energy Converter
- Power Converter
- Data Storage Converter
- Angle Converter
- Fuel Economy Converter
- Density Converter
- Flow Rate Converter
- Torque Converter
- Force Converter
- Frequency Converter
- Illuminance Converter
- Cooking Measurement Converter
- Foot Inch Converter
- Board Foot Converter
- Acreage Converter
Math & Geometry Calculators
31
View category
- Percentage Calculator
- Fraction Calculator
- Ratio Calculator
- Square Footage Calculator
- Circle Area Calculator
- Triangle Area Calculator
- Volume Calculator
- Slope Calculator
- Midpoint Calculator
- Distance Calculator
- Pythagorean Theorem Calculator
- Quadratic Equation Calculator
- Average Calculator
- Standard Deviation Calculator
- Permutation Calculator
- Combination Calculator
- Prime Number Calculator
- LCM Calculator
- GCD Calculator
- Percentage Change Calculator
- Percentage Difference Calculator
- Surface Area Calculator
- Cylinder Volume Calculator
- Sphere Volume Calculator
- Right Triangle Calculator
- Room Area Calculator
- Proportion Calculator
- Fraction to Decimal Calculator
- Decimal to Fraction Calculator
- Prime Factorization Calculator
- Scientific Notation Calculator
Student & Grade Calculators
12
Text Utilities
18
View category
- Word Counter
- Character Counter
- Reading Time Calculator
- Line Counter
- Sentence Counter
- Paragraph Counter
- Text Case Converter
- Duplicate Line Remover
- Word Frequency Counter
- Text Diff Calculator
- Slug Generator
- Letter Frequency Counter
- Syllable Counter
- Keyword Density Calculator
- Reading Level Calculator
- Whitespace Cleaner
- Password Strength Checker
- Text Reverser
Garden & Landscaping Calculators
8
Health & Body Calculators
3
Finance Calculators
7
Everyday Life Calculators
2
A little help before you calculate
About the projectAre these calculators free to use?
Yes. You can open a calculator and enter your values without a subscription or an account.
How do I find the right calculator?
Search for a task such as percentage, paint, or loan payment. You can also browse by category and compare each tool’s inputs and description.
How can I understand a calculation?
Calculator pages include explanations and guides for formulas, units, and worked examples. Check the inputs and assumptions when comparing results.
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