Ratio Calculator
Simplify ratios, solve for missing terms in proportions, and compare two ratios online.
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This online ratio calculator handles three core ratio operations: simplifying two numbers into reduced integer terms, solving for a missing proportion term, and comparing two ratios to determine which fraction is larger. In Simplify mode, enter values for A and B to reduce the ratio to its lowest whole-number terms using their greatest common divisor. In Missing mode, provide terms A, B, and C to solve for the missing fourth proportion value using the relationship of A times C divided by B, with results rounded to ten decimal places. In Compare mode, supply all four values to evaluate the relationship between the ratio A to B and the ratio C to D, displaying whether the first ratio is larger, smaller, or equal to the second ratio. Denominators B and D must be nonzero values so the calculation completes cleanly without division-by-zero errors.
Instructions
- Select a calculation mode: Simplify, Missing, or Compare.
- Enter the required numeric values for terms A, B, C, or D based on your selected operation.
- Click the calculate button to process your inputs.
- Review the simplified ratio, calculated proportion value, or comparison statement in the output area.
Examples
- Simplifying the ratio 12:18 reduces both numbers by their greatest common divisor to display 2:3.
- In Missing mode with A = 3, B = 4, and C = 8, the tool evaluates 3 multiplied by 8 divided by 4 to return 6.
FAQ
What happens if a zero is entered in a denominator position?
A zero in a denominator position prevents valid division, so you will need to enter a nonzero number for calculation.
How are decimal outputs formatted?
Calculated numeric values in Missing and Compare modes are rounded to ten decimal places.
Can I enter text values into the number fields?
Text entered into input fields is converted to numbers when possible, and unrecognized text entries are ignored.