Free Online Calculators That Show Their Working
All Calculator is a free collection of online calculators for maths, money, health, dates and unit conversions. Type in your numbers and the answer appears straight away, together with the formula and every step used to get there. You can check the result, learn the method, or copy the working into your homework or report.
There is nothing to download and no account to create. The calculators run in your browser, so the numbers you type are never sent to us or stored anywhere.
What You Can Calculate
Percentages
Work out a percentage of a number, find what percent one number is of another, or measure a percentage change between two values. The percentage calculator covers everyday questions like discounts, tips, pay rises and test scores. The reverse percentage calculator finds the original price before tax or a discount was applied.
Fractions and Numbers
Add, subtract, multiply and divide fractions and mixed numbers with the fraction calculator. Turn any decimal, including repeating decimals, into a fraction with the decimal to fraction calculator.
Maths
Find square roots, cube roots and simplified radicals with the square root calculator. Break any whole number into its prime factors with the prime factorization calculator. For anything else, there is a full scientific calculator with trigonometry, logarithms and powers.
Money and Business
Check the selling price and profit on a product with the markup calculator. Add or remove tax from a price with the sales tax calculator. Split a restaurant bill fairly with the tip calculator. Loan, mortgage and interest calculators show monthly payments and a full repayment schedule.
Health and Everyday Life
Find your body mass index and healthy weight range with the BMI calculator. Estimate how many calories you need each day with the calorie calculator. Work out your exact age in years, months and days with the age calculator.
Science and Technology
Solve speed, distance and time problems with the velocity calculator. Add, subtract and convert binary numbers with the binary calculator.
How Our Calculators Work
Every calculator follows the same simple pattern:
- Enter your numbers. Each box tells you what to type and in which unit.
- Get the answer instantly. The result updates as you type, with the main answer shown first.
- See the working. Open “Step-by-step working” to see the formula and each calculation in order.
Where it helps, you’ll also get a chart or a table. Loan calculators show a repayment schedule, the BMI calculator shows where your result sits on the scale, and the percentage tools show the result as a fraction.
Calculators that use measurements let you switch between US and metric units. Money calculators let you choose your currency. Your choice is remembered next time you visit.
Frequently Asked Questions
Are the Calculators Free?
Yes. Every calculator on the site is free to use, with no sign-up and no limit on how many times you use it.
How Accurate Are the Results?
The calculators use the standard formula for each calculation, and each formula is shown on the page so you can check it. Answers are rounded for display; the working shows the full figures.
Can I Use Them on My Phone?
Yes. Every calculator works on phones and tablets, and the layout adjusts to fit your screen.
Can I Share a Result?
Yes. Click “Share link” under any result to copy a link that opens the same calculator with your numbers already filled in.
Is My Information Stored?
No. Calculations happen in your browser. Nothing you type is sent to our server.