What this calculator does
Working out something like 32/40 as a percentage means asking what share of 40 the number 32 represents, expressed out of 100 instead of out of 40. The arithmetic is the same however the two numbers are dressed up: a test score, a survey result, a completed task count, a sports statistic.
This calculator takes any X out of Y ratio and converts it to a percentage, using 32 out of 40 as the example on this page but working identically for any two numbers entered.
The formula
Divide X by Y, then multiply by 100. That single calculation is the whole of it: 32 ÷ 40 = 0.8, and 0.8 × 100 = 80%, so 32 out of 40 is 80%.
| Term | Meaning |
|---|---|
| X | The amount or count being expressed as a share of the total. |
| Y | The total, or whole, that X is being measured against. |
| Percentage | (X ÷ Y) × 100, the share X represents out of every 100 parts of Y. |
The inputs explained
| Field | What to enter |
|---|---|
| X (the amount) | The amount, score or count you want to express as a percentage. |
| Y (the total) | The total or maximum possible value that X is out of. |
When to use it
Converting a test or exam score
A score like 32 out of 40 marks is far easier to compare against a grading scale, or against another test marked out of a different total, once it is converted to a percentage.
Reporting a survey or completion rate
When a fixed number of respondents, tasks or items are involved, expressing the completed or positive count as a percentage of the total puts it on a scale everyone reads the same way.
Comparing two different ratios fairly
A score of 24 out of 30 and a score of 27 out of 30 are only directly comparable to a score out of 40 once every figure is converted to the same percentage scale.
Worked examples
Every figure in the tables below is produced by this page’s own calculator at build time, so the numbers and the tool always agree. Select any row to load that scenario.
Common "X out of 40" scores as percentages
A fixed total of 40, across a range of scores.
The same score out of different totals
A fixed score of 24, measured against a range of different totals.
Questions
What is 32/40 as a percentage?
80%. Divide 32 by 40 to get 0.8, then multiply by 100.
What is 27/30 as a percentage?
90%. Divide 27 by 30 to get 0.9, then multiply by 100.
How do you turn a fraction into a percentage?
Divide the top number by the bottom number to get a decimal, then multiply that decimal by 100 and add a percent sign. The same rule applies whatever the two numbers happen to be.
Can X be bigger than Y?
Yes, and the result will simply be a percentage over 100%, which is a normal and correct outcome when X genuinely exceeds the total Y, such as exceeding a target by a certain amount.
For a percentage change between two values instead of a share of a total, see the percentage change calculator. For percentages of a value generally, see the percentage calculator.