Calculator
What the Ratio Simplifier does
Ratio Simplifier: calculates Simplified A/B and A ÷ B from Part A and Part B. Example: part a 2 and part b 3 gives simplified A/B 2/3.
Simplified A/B and A ÷ B, derived from Part A and Part B. You can nudge a single number and watch the effect straight away.
Most people who open the Ratio Simplifier are students checking homework. A second opinion on a calculation takes seconds and prevents errors compounding.
There is no account, no upload and no server round trip, because the page does the work itself.
If you want to check the arithmetic, the field table, the method and a worked example are further down.
What do the Ratio Simplifier fields mean?
The Ratio Simplifier uses 2 inputs. You do not have to fill everything in before seeing an answer; the starting values already produce one.
| Field | What to enter | Default |
|---|---|---|
| Part A | required | 2 |
| Part B | required | 3 |
How does the Ratio Simplifier work?
Each output is derived from the inputs above in a single pass; there is no hidden state carried between runs, so the same inputs always give the same calculation.
The guard clauses run before the formula does, which is why mistakes surface next to the field.
Worked example
These are the values the Ratio Simplifier loads by default, and the result it produces from them. This is the worked example the page starts from, reproduced here so you can check the arithmetic.
| Part A | 2 |
|---|---|
| Part B | 3 |
| Simplified A/B | 2/3 |
|---|---|
| A ÷ B | 0.666667 |
| What this means | Ratio A:B simplifies to 2:3 |
Beyond the formula: reducing a ratio to lowest terms
Simplifying a ratio means dividing both terms by their greatest common divisor, and the classical way to find that divisor is Euclid’s algorithm: repeatedly replace the larger term with the remainder of dividing it by the smaller, until the remainder reaches zero.
Common mistakes and sanity checks
- Euclid’s algorithm on a screen resolution shows the mechanics clearly: 1920 and 1080 give remainders 840, then 240, then 120, then 0, so the GCD is 120 and 1920:1080 reduces to the familiar 16:9.
- Two terms sharing no common factor beyond 1 are called coprime, and a ratio of coprime terms is already in lowest terms. 16:9 cannot reduce further, which is why aspect ratios are quoted in that form rather than as the raw pixel counts.
- Ratios written with decimals or fractions have to be scaled to whole numbers before the GCD means anything: 2.5:4 becomes 5:8 by multiplying both sides by 2, and only then can it be reduced.
How to use it
- Fill in Part A.
- Type Part B.
- Watch the results panel as you type: it recalculates on every keystroke.
- The panel reports Simplified A/B, A ÷ B and What this means.
- Copy Link puts the current inputs in the URL, so bookmarking it brings the same numbers back.
What this tool does not do
- Displayed values are rounded; the underlying calculation keeps full precision.
- Very large or very small values reach the limits of floating-point precision, about 15 significant digits.
- The method is fixed. There is no option to substitute your own formula.
Frequently asked questions
Part A and Part B. That is the whole form. Every box already holds a working value, letting you treat it as a what-if tool rather than a data-entry form.
With the values loaded when the page opens, simplified A/B comes out as 2/3. The figure is derived from the inputs above, so it updates whenever they do.
Nothing is stored. The page has no back end to send data to, and holds your input only in memory.
No. There is no account, no usage cap and no trial period. The site is funded by advertising rather than by charging for the tools.
Reliable for the case described. Where more than one convention exists, the method section says which one is used.