Maths calculators ยท free, runs on your device
Ratio calculator: simplify, share and solve.
Simplify a ratio such as 12:18:24, split money or ingredients in a ratio, or find the missing number in a proportion.
Three things you can do with ratios
- Simplify: divide every part by their highest common factor. 12 : 18 : 24 becomes 2 : 3 : 4.
- Share: add the parts, divide the total by that, then multiply by each part. Sharing โน50,000 between partners in the ratio 3 : 2 gives โน30,000 and โน20,000.
- Solve a proportion: if a : b = c : x then x = b ร c รท a. If 2 kg of rice serves 3 families, 10 kg serves 15.
Ratios appear in recipes (scale every ingredient by the same factor), maps (1 : 50,000), mixing paint and concrete, and gearing. Use the percentage calculator to turn a share into a percentage.
FAQ
Common questions
How do I simplify a ratio?
Divide all the numbers by their highest common factor. If the ratio has decimals, multiply them all by 10 or 100 first to make whole numbers.
How do I divide an amount in a ratio?
Add the ratio parts to get the total number of shares, divide the amount by this total to get one share, then multiply by each part.
What is the difference between a ratio and a fraction?
A ratio compares parts to each other (3 : 2), while a fraction compares a part to the whole (3/5 and 2/5). They are closely linked: a 3 : 2 ratio means shares of 3/5 and 2/5.
More free tools
Keep going
Percentage calculator
Find X% of a number, what percent one number is of another, percentage change, add or take off a percentage, and reverse percentages.
Use the tool โFraction calculator
Add, subtract, multiply and divide fractions and mixed numbers, with the answer simplified and the working shown step by step.
Use the tool โLCM & HCF calculator
Find the lowest common multiple and highest common factor (GCD) of up to eight numbers, with a prime factor table that shows why.
Use the tool โPrime number checker
Check whether a number is prime, see its prime factorisation, all its factors, the nearest primes, or list every prime up to 100,000.
Use the tool โQuadratic equation solver
Solve axยฒ + bx + c = 0 with the discriminant, both roots (including complex ones), the vertex and the factorised form, step by step.
Use the tool โMean, median & mode calculator
Mean, median, mode, range, quartiles and standard deviation for any list of numbers, such as marks, prices, runs or temperatures.
Use the tool โStart a conversation
Questions about classes?
A parent or guardian can share the learner's age, level and goals, and we'll suggest a starting point.
- Tell us the learnerโs age or grade and goals
- Weโll suggest a suitable class or learning path
- Weโll confirm format, timing and fees with a parent or guardian
Play it, don't just read it
Try it now: Simplifying ratios
Eight quick questions with instant feedback. Your score is saved on this device and counts in the games and learning paths too.
Simplifying ratios (Grade 6): Writing a ratio in its simplest form. Open the practice page or print a worksheet.
Or play a game
- Decimal DetectivesFind the decimal point, line up place values and solve decimalโฆPlay
- Integer IslandNavigate positive and negative numbers with addition, subtraction,โฆPlay
- Estimation StationEstimate big sums without a calculator and see how close you get.Play