Quick guide
How to use this calculator
- Choose the real storage, transfer, media, backup, or archive task first, then enter only the measurements and assumptions that belong to that workflow.
- Keep bits and bytes, decimal SI and binary IEC prefixes, rates, durations, counts, reserves, efficiency, overhead, compression, and retention conventions explicit.
- Use the companion outputs to reconcile the scenario. Where actual system behavior is unknown, enter measured values or retain the stated limitation instead of treating a plan as a guarantee.
Calculation method
How the compression ratio and space savings calculator works
Compare observed or scenario file sizes without assigning an unverified compression ratio to a file format, codec, archive tool, or dataset.
Compression ratio = original size ÷ compressed size. Space saved = original − compressed; reduction percentage = saved ÷ original × 100; retained percentage = compressed ÷ original × 100.
Worked example
Compression Ratio and Space Savings example
Reducing 10 GB to 2.5 GB gives a 4:1 ratio, saves 7.5 GB, retains 25% of the original size, and reduces storage by 75%.
Compression ratio = original size ÷ compressed size. Space saved = original − compressed; reduction percentage = saved ÷ original × 100; retained percentage = compressed ÷ original × 100.
Supported inputs
Precision and limits
Digital-system boundary
A ratio below 1 means the result expanded rather than compressed. The calculator compares quantities only and does not predict quality loss, reversibility, speed, security, codec suitability, or achievable ratios.
Units and precision
One byte is eight bits. Decimal kB, MB, GB and TB use powers of 1,000; binary KiB, MiB, GiB and TiB use powers of 1,024. Calculations retain working precision and round only for display.
Category ownership
This calculator handles neutral information quantity, transfer, storage, media-payload, compression, backup, RAID, or archive arithmetic. Live speed tests, IP addressing, packet engineering, current vendor pricing, security analysis, and physical display sizing belong to other tools.
Privacy
File names and contents are never requested. Entered quantities and results stay in this browser and are not sent to analytics or third parties.
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