Ratio Calculator
Simplify a two-part ratio and compare its decimal value and percentage shares.
Tool code processes selected files and entered content in your browser and does not submit them to a TOOLGRID processing endpoint. TOOLGRID measures tool usage, not the content you enter.
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What this tool does
Simplify two numeric values into a colon ratio, calculate left divided by right, and show each side as a share of their sum. Decimal inputs are scaled to at most six places before greatest-common-divisor reduction.
Ratio Calculator presents the same comparison four ways: simplified left:right, left divided by right, left share of the total, and right share of the total.
For 16 and 9 the simplified ratio remains 16:9, the decimal comparison is about 1.7778, and the shares are 64% and 36% of the combined 25 parts.
Use values with the same unit and non-negative meaning when interpreting shares; mixed signs or a zero-sum pair can produce mathematically valid ratios that are not useful allocations.
Where this tool earns its place
Simplify pixel dimensions such as 1920:1080 to 16:9 before documenting an image or video requirement.
Reduce two ingredient quantities to a reusable proportion after converting both values to the same unit.
Show both the part-to-part ratio and each side's percentage of the combined total for a budget or sample split.
What to check before relying on the result
- Performance and maximum practical input size depend on browser memory, device speed, and the structure of the input.
- Review the generated result before replacing or publishing an original file.
Open a nearby browser tool when you need to validate, convert, or reuse the result.
How to use
01Use Cases
Simplify pixel dimensions such as 1920:1080 to 16:9 before documenting an image or video requirement.
Reduce two ingredient quantities to a reusable proportion after converting both values to the same unit.
Show both the part-to-part ratio and each side's percentage of the combined total for a budget or sample split.
Tips & Tricks
- 01Convert units first
A ratio between 1 meter and 50 centimeters should be entered as 100:50 or 1:0.5, not 1:50.
- 02Expect six-place normalization
Decimal simplification scales at most six fractional places before rounding to integers, so higher-precision inputs may reduce approximately.
- 03Interpret zero carefully
A right side of zero produces an infinite decimal ratio. When the two sides sum to zero, percentage shares are shown as 0% because allocation is undefined.
FAQ
02Can both values be zero?
No. At least one side must be non-zero.
What is a simplified ratio?
Both values are divided by their greatest common divisor, so 4:6 becomes 2:3.
Can I use decimal inputs?
Yes. The calculator scales decimal inputs to integers using up to six decimal places, then reduces them with the greatest common divisor.
What happens when the right value is zero?
The simplified ratio is still shown and the decimal left-to-right value is infinity. Percentage shares remain meaningful only when the combined total is non-zero.
Do the two percentage shares always add to 100%?
They do for ordinary non-negative values with a non-zero total, subject to display rounding. Mixed signs and a zero-sum pair are not meaningful allocation inputs.