Gigabyte to Megabyte (GB to MB)
Convert GB to MB — Data Storage converter
1 GB = 1000 MB (decimal SI).
A gigabyte (GB) is 1000 megabytes (MB) under the decimal SI definition this converter uses, so to convert gigabytes to megabytes you multiply by 1000.
There are two conventions, which is the usual source of confusion. Storage makers, networks, and SI use decimal (1 GB = 1000 MB). Operating systems like Windows and figures for RAM use binary, where 1 GiB = 1024 MiB — that gap is why a "1 TB" drive can show as about 931 GB in your file manager.
1 GB = 1000 MB
Gigabyte to Megabyte formula
1 Gigabyte = 1000 MB
Worked examples
- 25 GB = 25000 MB
- 100 GB = 100000 MB
Common uses
- Sizing files, downloads, and storage
- Comparing quoted drive capacity to what the OS reports
- Working out data-cap and bandwidth usage
Gigabyte to Megabyte conversion table
| Gigabyte (GB) | Megabyte (MB) |
|---|---|
| 1 | 1000 |
| 2 | 2000 |
| 3 | 3000 |
| 5 | 5000 |
| 8 | 8000 |
| 10 | 10000 |
| 12 | 12000 |
| 15 | 15000 |
| 20 | 20000 |
| 25 | 25000 |
| 50 | 50000 |
| 100 | 100000 |
| 250 | 250000 |
| 500 | 500000 |
| 1000 | 1000000 |
Frequently asked questions
How many MB are in a GB?
1 GB = 1000 MB using the decimal (SI) definition. In binary units, 1 GiB = 1024 MiB.
What is 1 GB in MB?
1 GB = 1000 MB (decimal).
Why does my drive show less space than advertised?
Makers count decimal GB (1000 MB), but the OS often counts binary (1024 MiB), so the reported number is smaller.
Is a gigabyte 1000 or 1024 megabytes?
It depends on the convention: 1000 in decimal SI (used here), 1024 in binary. Both are in common use.