GB to GiB Converter

About this calculator

The confusion between GB and GiB comes down to two different definitions of “giga.” Storage manufacturers and most marketing materials use the decimal definition, 1 GB = 10⁹ bytes (1,000,000,000 bytes), following the SI prefix system. Operating systems and file managers, on the other hand, often report sizes using the binary definition, 1 GiB = 2³⁰ bytes (1,073,741,824 bytes) — which is roughly 7.4% larger than a GB.

That mismatch is exactly why a “1 TB” hard drive shows up as roughly 931 GiB in Windows' file explorer. This converter switches between the two so IT professionals, developers, and anyone puzzled by a drive that looks smaller than advertised can see precisely where the missing space actually went — it isn't missing at all, just measured differently.