How to calculate data storage
Convert everything to bytes first, then divide by the target unit
Worked example. In bytes: 500,000,000 B.
Example inputs — Amount: 500; Unit: Megabytes (MB). Starting values are illustrative.
From George Guju, founder of Calculyn · Educational calculator guidance, not professional advice.
How it works
Storage makers use decimal units (1 GB = 1 billion bytes) while operating systems often show binary units (1 GiB = 1,073,741,824 bytes) — which is why a 500 GB drive shows about 465 GiB.
Assumptions & limitations
- Results are rounded for display.
Formula and assumptions reviewed October 2026 by the Calculyn team. How we build our calculators
Frequently asked questions
Why does my drive show less space than advertised?
Drives are sold in decimal GB but computers often display binary GiB, which are about 7% larger per unit.