Compression Savings Estimator

Estimate compressed sizes and savings.

Runs in your browser. Nothing is uploaded — your input is processed on this device and discarded when you close the tab.

Compression Savings Estimator

How to use this tool

  1. Enter your values in the fields above.
  2. Press Generate to see the result.
  3. Use Load sample to try the worked example, Copy result to copy it, or Clear to start again.

Worked example

A 100 KB HTML file is estimated at about 25 KB with gzip (75% saved) and about 20 KB with Brotli (80% saved), using typical ratios for text files.

What this tool does not do / Limits

These are estimates from typical ratios, not measurements of your file. Real savings vary with content, and already-compressed formats such as pictures save far less.

Frequently asked questions

Why do text files compress so well?

Text repeats patterns and words, which compression algorithms replace with short references.

Is Brotli always smaller than gzip?

Usually for text, yes, but the gap varies and both depend on the exact content.

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