GB to MB Converter
Type gigabytes to get megabytes. Switch to binary for the 1024-based figure used for RAM and by Windows.
4 GB =
4,000MB
4 gigabytes is 4,000 megabytes.
- In binary units (1024)
- 4,096 MiB
- 1 GB
- 1,000 MB
- 1 MB
- 0.001 GB
How to convert GB to MB
Multiply gigabytes by 1,000 to get megabytes. A 15 GB monthly data plan is 15,000 MB, so a 150 MB app update uses one hundredth of it.
Computer memory is the exception. RAM is built in powers of two, so a “16 GB” laptop really has 16 GiB, and 16 × 1,024 = 16,384 MiB. That is why system tools list memory as 16,384 MB rather than 16,000.
Video streaming and app stores quote sizes in GB too. To check what fits in what is left of a plan, convert everything to MB first, then add: a 1.2 GB film plus three 150 MB updates is 1,200 + 450 = 1,650 MB.
megabytes = gigabytes × 1,000
- Under the SI, giga means 10⁹ and mega 10⁶ whatever the unit, so 1 GB is 1,000 MB; the binary 1,024 belongs to the gibibyte (GiB) and mebibyte (MiB). Source: NIST, Prefixes for binary multiples (IEC 80000-13).
How to estimate GB to MB in your head
Add three zeros: 2.5 GB is 2,500 MB and 0.3 GB is 300 MB. For memory sizes, add about 2.4% on top: 8 GiB of RAM is 8,192 MiB, so “a little over 8,000” is the right feel.
Gigabytes to megabytes chart
Plan, download and memory sizes in GB, with megabytes in both conventions.
| Gigabytes | Megabytes (× 1000) | GiB → MiB (× 1024) |
|---|---|---|
| 0.1 | 100 | 102.4 |
| 0.25 | 250 | 256 |
| 0.5 | 500 | 512 |
| 1 | 1,000 | 1,024 |
| 1.5 | 1,500 | 1,536 |
| 2 | 2,000 | 2,048 |
| 3 | 3,000 | 3,072 |
| 4 | 4,000 | 4,096 |
| 5 | 5,000 | 5,120 |
| 6 | 6,000 | 6,144 |
Show all 20 rowsShow fewer
| 8 | 8,000 | 8,192 |
| 10 | 10,000 | 10,240 |
| 12 | 12,000 | 12,288 |
| 15 | 15,000 | 15,360 |
| 16 | 16,000 | 16,384 |
| 20 | 20,000 | 20,480 |
| 32 | 32,000 | 32,768 |
| 50 | 50,000 | 51,200 |
| 64 | 64,000 | 65,536 |
| 100 | 100,000 | 102,400 |
Frequently Asked Questions
How many MB are in 4 GB?
4 GB is 4,000 MB. If the 4 GB is a memory stick or RAM size counted in binary, it is 4,096 MiB.
How many songs or photos fit in 1 GB?
Divide 1,000 MB by the typical file size. With 5 MB photos, about 200 fit; with 4 MB songs, about 250. Your own files vary, so check one and divide.
Why does RAM use 1024?
Memory chips are addressed by binary numbers, so their sizes land on powers of two. 2³⁰ bytes is the natural “gigabyte” of memory, and the IEC name for it is the gibibyte.