MB to GB Converter — Megabytes to Gigabytes
An MB to GB converter divides a size in megabytes into gigabytes — the direction you need when your usage meter, file manager or billing page counts in MB but the quota is written in GB.
Quick answer: Divide by 1,024 to get binary GB (what Windows shows) or by 1,000 to get decimal GB (what vendors quote). 1,000 MB is 0.977 GiB but exactly 1 GB decimal — the two results differ by 2.4%.
The two lines are the same file — only the definition of “GB” differs. This 2.4% gap per step is why a 1 TB drive shows 931 GiB in Windows.
| MB | GB |
|---|---|
| 0.5 | 0.000488281 |
| 1 | 0.000976563 |
| 2 | 0.00195313 |
| 5 | 0.00488281 |
| 10 | 0.00976563 |
| 50 | 0.0488281 |
| 100 | 0.0976563 |
| 500 | 0.488281 |
| 1,000 | 0.976563 |
| Binary rule | 1 GB = 1,024 MB, so 1 MB = 0.000977 GB |
|---|---|
| Decimal rule | 1 GB = 1,000 MB, so 1 MB = 0.001 GB |
| Handy anchor | 1,024 MB = 1 GiB · 1,000 MB = 1 GB decimal |
| Typical MB sizes | Word document ~0.3 MB · photo 3–8 MB · song 4–8 MB · minute of 1080p video ~110 MB |
Dividing makes the gap visible
Converting MB down to GB is the direction where the two conventions are easiest to compare: 500 MB is 0.488 GiB or exactly 0.5 GB decimal, and 3,000 MB is 2.93 GiB or 3.00 GB decimal. If your phone's hotspot shows 3,000 MB used and your plan is 3 GB, the same traffic can look like an overage under one rule and a perfect fit under the other — which is why carriers bill decimal.
Reading data-usage screens correctly
Android and iOS traffic meters report in MB and GB using binary arithmetic, while carriers bill decimal. A month of 12,000 MB of traffic is 11.7 GiB to your phone and exactly 12.0 GB to your carrier. Keep a 3–5% mental buffer at the end of a billing cycle if you are close to the cap.
How to enter a conversion the calculator can use
Values below 1 GB convert to fractions of a GB (0.5, 0.47), and values above 1,000 MB are easiest to read as GiB. The tool takes either: type 1,500 MB and read both results — 1.465 GiB (binary) and 1.5 GB (decimal).
When to use this calculator
- Comparing hotspot usage in MB against a plan quoted in GB.
- Converting an email attachment limit (25 MB) into the fraction of a GB it consumes.
- Estimating how many photos (MB each) will fill a GB of cloud storage.
- Reading router traffic statistics that use MB while your ISP quota uses GB.