Convert gibibytes to mebibytes

One gibibyte is 1024 mebibytes. To convert any amount, multiply by 1024. Going the other way, one mebibyte is 0.0009765625 gibibytes.

Multiply the gibibyte figure by 1024. So MiB = GiB × 1024. For a quick mental estimate, multiplying by about 1024 gets you within a percent or so, which is close enough for most everyday purposes.

One gibibyte is what your OS calls a 'GB' of memory. A gibibyte is exactly 1,024³ bytes, about 7.4% more than a gigabyte. RAM is always sold in binary units even when storage is not.

One mebibyte is about 5% more than a megabyte. A mebibyte is exactly 1,024² bytes. The binary prefixes — kibi, mebi, gibi — were standardised by the IEC in 1998 precisely to end the ambiguity, though adoption is patchy.

Because two different definitions are in play. Storage manufacturers use decimal units — 1 TB means exactly one trillion bytes. Windows and many other systems display binary units but label them with decimal names, so they show that same drive as 931 "GB" when they mean 931 gibibytes. Nothing is missing and nothing is faulty; the drive holds exactly what it says, measured differently. The IEC standardised kibi, mebi and gibi in 1998 specifically to end this, but adoption has been patchy.

Yes — both decimal and binary prefixes are exactly defined powers, so every figure here is exact rather than approximate. The results are shown to seven significant figures; the underlying arithmetic uses full double precision.