Skip to the calculator
Rule Calculator

Convert Gigabytes to Megabytes

1 gigabyte is 1,000 MB. One gigabyte is exactly 1000 megabytes.

One gigabyte is 1000 megabytes. To convert gigabytes to megabytes, multiply by 1000; to go the other way, divide by 1000 or multiply by 0.001. The factor is exact rather than rounded: it follows from IEC 80000-13. Exactly one billion bytes.

Factor checked against the defining standard · How we check

Megabytes
1,000 MB
Gigabytes × 1000
value * 10001,000 MB

1 gigabyte in every data unit

UnitValueExact factor
bytes1,000,000,000 B× 1,000,000,000
kilobytes1,000,000 kB× 1,000,000
megabytes1,000 MB× 1,000
gigabytes (as entered)1 GB
terabytes0.001 TB× 0.001
kibibytes976,562.5 KiB× 976,562.5
mebibytes953.6743164 MiB× 953.674316406
gibibytes0.9313225746 GiB× 0.931322574615

Factors are entered by hand from IEC 80000-13 rather than derived from a units library, so the ones that terminate are exact rather than rounded.

How do you convert gigabytes to megabytes?

  1. 1.Take the measurement in gigabytes.
  2. 2.Multiply by 1000 — that is how many megabytes fit in one gigabyte.
  3. 3.To go back the other way, divide by 1000, or multiply by 0.001.

Gigabytes to megabytes conversion table

GigabytesMegabytes
1 GB1,000 MB
2 GB2,000 MB
3 GB3,000 MB
4 GB4,000 MB
5 GB5,000 MB
6 GB6,000 MB
7 GB7,000 MB
8 GB8,000 MB
9 GB9,000 MB
10 GB10,000 MB
12 GB12,000 MB
15 GB15,000 MB
20 GB20,000 MB
25 GB25,000 MB
50 GB50,000 MB
100 GB100,000 MB

What are gigabytes and megabytes?

Gigabyte (GB)
Exactly one billion bytes. This is why a "1 TB" drive shows as roughly 931 GB in Windows: the drive is sold in decimal and displayed in binary.
Megabyte (MB)
Exactly one million bytes. A file manager showing a smaller number for the same file is counting in mebibytes.

Source: IEC 80000-13 — binary prefixes for information quantities

Questions people actually ask

How many megabytes are in a gigabyte?
1000. Exactly one million bytes. A file manager showing a smaller number for the same file is counting in mebibytes.
How do I convert megabytes back to gigabytes?
Divide by 1000, or multiply by 0.001 — they are the same operation.

Other data conversions

Megabytes to gigabytes — the same conversion the other way.