The Ratio Calculator is a free tool that helps you calculate ratio using the formula Simplify A:B by their GCD; scale proportionally if a target is given. Enter your values above and press Calculate to get simplified ratio, scaled b instantly, with a full step-by-step breakdown.
What is the Ratio Calculator?
The ratio calculator is a free online tool that helps you calculate ratio quickly and accurately. It applies the standard formula Simplify A:B by their GCD; scale proportionally if a target is given to the values you enter and, when you press Calculate, displays the result together with a clear, step-by-step explanation of how the answer was reached.
How to use the Ratio Calculator
- Enter the two terms.
- Optionally scale term A to a new value.
- See the simplified and scaled ratio.
Formula used
The ratio calculator is based on this formula:
Simplify A:B by their GCD; scale proportionally if a target is givenEach term in the formula corresponds to one of the inputs explained below. The calculator performs the arithmetic for you and shows every step so you can check the working by hand if you wish.
Worked example
Suppose you enter 4:6. The calculator works as follows:
| Inputs | 4:6 |
|---|---|
| Working | divide by 2 |
| Result | 2:3 |
Step-by-step calculation
- Apply the formula:
Simplify A:B by their GCD; scale proportionally if a target is given - Substitute your values: divide by 2
- Read the result: 2:3
Inputs explained
- Term A — the term a used in the calculation.
- Term B — the term b used in the calculation.
- Scale A to — the scale a to used in the calculation.
Understanding your result
- Simplified ratio — the calculated simplified ratio.
- Scaled B — the calculated scaled b.
Benefits and practical uses
The ratio calculator saves time and removes the risk of manual errors when you need to calculate ratio. It is useful for students, professionals and anyone who wants a fast, dependable answer. Results update the moment you press Calculate, work on any device, and can be copied or shared in a single click — and because the maths runs in your browser, your figures stay completely private.
Tips for an accurate result
- Keep all related inputs in the same units.
- Use the worked example above to confirm you are entering values in the right places.
- Review the assumptions below so the result fits your situation.
- Press Reset to clear everything and try a different scenario.
Common mistakes to avoid
- Entering values in the wrong unit (mismatched units give wrong answers).
- Leaving a required field empty — the calculator will ask you to fill it in.
- Rounding inputs too early, which can slightly change the result.
Assumptions and limitations
- Positive terms.
Frequently asked questions
How do I simplify a ratio?
Divide both terms by their greatest common divisor.
How do I use the Ratio Calculator?
Enter your values in the fields, then press the Calculate button to see the result. Use Reset to clear the form and start again. Nothing is calculated until you click Calculate.
What formula does the Ratio Calculator use?
It uses the standard formula: Simplify A:B by their GCD; scale proportionally if a target is given. The full step-by-step working is shown with every result so you can verify it.
What information do I need to use the ratio calculator?
You need: term a, term b, scale a to. Sensible example values are pre-filled so you can see how it works.
Is the Ratio Calculator free to use?
Yes. Every DigiToolkit calculator is completely free, with no sign-up, no login and no usage limits.
Does the Ratio Calculator work on mobile phones?
Yes. The calculator is mobile-first and works on phones, tablets and computers in any modern browser.
Do I need to install an app?
No. The ratio calculator runs directly in your web browser — there is nothing to download or install.
Is my data private when I use this calculator?
Yes. All calculations run inside your browser. The numbers you enter are never uploaded to a server or shared with anyone.
How accurate is the Ratio Calculator?
It uses the generally accepted formula for ratio and computes to several decimal places. Results are accurate for the assumptions listed on this page.
Can I copy or share my result?
Yes. After calculating, use the Copy button to copy the result, or Share to copy the page link.
Why is nothing showing until I press Calculate?
By design, the calculator only computes when you press Calculate, so you can finish entering all your values first. Press Reset any time to clear everything.