Ratio Calculator (Percentage & Composition)
Calculate the percentage (%) from a part and a whole, work backward to find a part from a percentage, or break down multiple items into a composition ratio shown in a table.
Input
Calculation type
Example: for a test scored "24 correct out of 30", enter part = 24 and whole = 30 to get the score rate.
Result
Percentage
25%
Part value
30
Whole value
120
Percentage
25 %
How it works
- "Find percentage (%)" divides the part value by the whole value and multiplies by 100. It works directly for test score rates and completion rates.
- "Find the part" multiplies the whole value by a percentage (%). For example, you can quickly check the amount or count that equals 15% of the whole.
- "Composition ratio" lets you enter several items and shows each item's share (%) of the total in a table, highlighting the largest item in color.
- Add items with the "Add item" button and remove unneeded rows with the ✕ button. This view is ideal for comparing breakdowns such as population by region or sales mix.
- The composition ratio divides each item against a total treated as 100%, so rounding may cause the sum to differ slightly from 100.0%.
- Decimal values are accepted and results are shown to about two decimal places. A percentage cannot be calculated when the whole value is 0.
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