The Calc Studio — Free Online Calculators
The Calc Studio provides 205 free online calculators and practical tools for everyday questions. The catalog covers math, finance, business, health and fitness, dates and time, science, construction, measurements, and utility tasks. Each calculator is designed to give a direct result while the supporting pages explain the formula, assumptions, worked examples, and common limitations.
You can use the calculators without creating an account. Where a calculation depends on assumptions, the page explains what the formula does and what it does not represent. This makes the site useful both for a quick numerical check and for learning how a calculation works.
Popular starting points
- Percentage Calculator — Calculate percentages, percentage of a number, and percentage change between two values.
- Age Calculator — Calculate your exact age in years, months, and days from your birth date.
- BMI Calculator — Calculate your Body Mass Index (BMI) and see which weight category you fall into.
- Tip Calculator — Split bills and calculate tips with customizable tip percentages.
- Salary Calculator — Convert between hourly, daily, weekly, monthly, and annual salary.
- Discount Calculator — Calculate the final price after a discount and see how much you save.
- Sales Tax Calculator — Calculate sales tax and final price for any amount and tax rate.
- CAGR Calculator — Calculate compound annual growth rate between a starting value and ending value.
Browse the calculator topic directory to follow related math, date, business, health, construction, science, and conversion tools.
Browse by category
- Financial Calculators — 19 calculators. Free financial calculators for VAT, unit prices, overtime pay, rent splits, tips, discounts, salary, fuel costs, budgeting, inflation, net worth, and total-return metrics.
- Business Calculators — 27 calculators. Free business calculators for profit margin, depreciation, unit pricing, ROI, markup, break-even points, and sales commissions.
- Math Calculators — 72 calculators. Free math calculators for percentage-point changes, interquartile range, percentages, fractions, ratios, averages, primes, bases, LCM/GCD, Roman numerals, and scientific calculations.
- Health & Fitness Calculators — 13 calculators. Free health and fitness calculators for BMI, calories, body fat, water intake, ideal weight, macros, pace, and pregnancy dates.
- Date & Time Calculators — 10 calculators. Free date and time calculators for age, date differences, date arithmetic, time zones, countdowns, and durations.
- Construction Calculators — 26 calculators. Free construction calculators for square footage, concrete volume, material estimates, and practical building measurements.
- Science & Electronics Calculators — 23 calculators. Free science and electronics calculators for density, Ohm's law, voltage drop, electrical power, and practical physical relationships.
- Everyday Tools — 15 calculators. Free everyday tools for unit conversion, random numbers, passwords, and QR codes.
Common calculation questions
For more detailed explanations, visit the calculator guides, calculator glossary, unit converters, and task-based collections. These pages provide context around the formulas and help you choose the right tool for a particular job.
Choose a practical calculation path
- Calculators for Students — Free calculators for students, including grades, GPA, percentages, fractions, interquartile range, averages, probability, statistics, and scientific math.
- Everyday Money Calculators — Free money calculators for salaries, overtime, discounts, VAT, sales tax, unit prices, rent splits, fuel costs, inflation, net worth, and other everyday calculations.
- Home Project Calculators — Free home and construction calculators for square footage, roofing, stairs, tile, mulch, gravel, concrete, drywall, decking, and material estimates.
- Health & Fitness Calculators — Free health and fitness calculators for BMI, BMR, calories, macros, body fat, water intake, ideal weight, waist-to-hip ratio, and pace.
- Business & Work Calculators — Free calculators for business and work, including ROI, markup, break-even, sales commission, salary, overtime, VAT, depreciation, profit margin, and practical percentage calculations.
- Time & Date Calculators — Free time and date calculators for age, date differences, date arithmetic, business days, time duration, time zones, and countdowns.
- Math & Statistics Calculators — Free math and statistics calculators for percentages, percentage-point change, interquartile range, averages, fractions, probability, standard deviation, z-scores, geometry, equations, and number systems.
- Science & Electronics Calculators — Free science and electronics calculators for density, electrical power, electricity costs, fuel efficiency, voltage drop, Ohm's law, and practical measurement relationships.
Need a reusable workflow? Premium can save calculation history and remove promotional blocks while the core calculators remain free to use.
Explore more calculation resources
Keep exploring related tools, explanations, conversions, and topic pages in The Calc Studio. These links are selected around the subject of this page so you can move to the next useful calculation without returning to search.
Related calculators
- Age Calculator — Calculate your exact age in years, months, and days from your birth date.
- BMI Calculator — Calculate your Body Mass Index (BMI) and see which weight category you fall into.
- Percentage Calculator — Calculate percentages, percentage of a number, and percentage change between two values.
- Date Difference Calculator — Find the exact number of days, months, and years between any two dates.
- Tip Calculator — Split bills and calculate tips with customizable tip percentages.
- Salary Calculator — Convert between hourly, daily, weekly, monthly, and annual salary.
Task collections
- Everyday Money Calculators — Free money calculators for salaries, overtime, discounts, VAT, sales tax, unit prices, rent splits, fuel costs, inflation, net worth, and other everyday calculations.
- Calculators for Students — Free calculators for students, including grades, GPA, percentages, fractions, interquartile range, averages, probability, statistics, and scientific math.
- Business & Work Calculators — Free calculators for business and work, including ROI, markup, break-even, sales commission, salary, overtime, VAT, depreciation, profit margin, and practical percentage calculations.
- Health & Fitness Calculators — Free health and fitness calculators for BMI, BMR, calories, macros, body fat, water intake, ideal weight, waist-to-hip ratio, and pace.
Related guides
Related terms
- Percentage — Understand what a percentage means, how percentages are calculated, and when to use a percentage calculator.
- Percentage Change — Learn what percentage change means, how to calculate increases and decreases, and how the original value affects the result.
- Percent Difference — Understand percent difference, when it is appropriate, and how it differs from percentage change and percent error.
Useful conversions
- cm to feet — Convert centimeters to feet with a free cm to feet converter, formula, examples, and a quick reference table.
- kg to lbs — Convert kilograms to pounds quickly and accurately with a free kg to lbs converter, formula, and reference table.
- lbs to kg — Convert pounds to kilograms with a free lbs to kg converter, formula, examples, and common-value reference table.
Browse all calculators · Read all guides · Open the glossary · See all converters · Browse collections
Want to keep learning? Move from a calculator to its formula guide, glossary definition, unit conversion, or task collection to compare related methods and tools.
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