MB to GB Converter

This converter uses 1 GB = 1,000 MB, the decimal SI definition:

gigabytes = megabytes ÷ 1000

That is not the only answer in circulation, and the ambiguity is genuine rather than pedantic.

Two systems, both in active use:

	Definition	Used by
Decimal (SI)	1 GB = 1,000 MB	Drive manufacturers, network speeds, macOS, Linux
Binary	1 GiB = 1,024 MiB	Windows, RAM, some software

Computers address memory in powers of two, so 1,024 is the natural unit internally. Storage and networking standardised on powers of ten. Both are correct within their own convention, and nobody is going to reconcile them.

This is why a "1 TB" drive shows as 931 GB in Windows. The manufacturer sold you 1,000,000,000,000 bytes, which is exactly what it says. Windows divides by 1,024 three times and reports 931 GiB — while labelling it "GB". The drive is not short; the two figures are the same bytes described differently.

The strictly correct binary units are KiB, MiB, GiB (kibibyte, mebibyte, gibibyte), standardised by the IEC in 1998. Almost nobody outside Linux uses them.

Practical sizes:

• A photo, 5 MB → 0.005 GB
• An album, 100 MB → 0.1 GB
• An HD film, 4,000 MB → 4 GB
• A mobile data plan, 25,000 MB → 25 GB

To convert back, multiply by 1,000 — or by 1,024 if you are matching what Windows displays.