File Compression Ratio Calculator
Compares a file before and after compression.
Compression ratio
— : 1
Share sends a link that reopens these numbers. Copy details pastes the full breakdown as a list.
Space saving — %
Space saved —
Reading this —
The formula
ratio = original ÷ compressed saving = 1 − compressed ÷ original
Make sure both sizes use the same kind of unit, either decimal or binary.
What to watch out for
A ratio of 4:1 and a saving of 75% are the same result.
Frequently Asked Questions
What is 500 MB compressed to 125 MB?
A ratio of 4:1, saving 75%.