Digital storage sizes — from a small text file to a modern hard drive — span an enormous range, and the units used to describe them (KB, MB, GB, TB) can be a source of confusion, partly because two different counting conventions exist.
The formula
For 1 GB converted to MB: 1 × 1,024 = 1,024 MB.
Binary vs. decimal storage units — the source of confusion
Storage manufacturers often market capacity using decimal (1000-based) units, so a "1 TB" drive is advertised using 1,000-based math, while your operating system typically reports size using the binary (1,024-based) convention this calculator uses — which is why a "1 TB" drive often shows up as roughly 931 GB in your file explorer. Neither figure is wrong; they're just different counting conventions applied to the same physical storage.
Worked examples
| From | To | Result |
|---|---|---|
| 500 MB | GB | 0.49 GB |
| 2 TB | GB | 2,048 GB |
| 4,096 KB | MB | 4 MB |
Common mistakes
- Assuming all storage math is 1000-based. File systems and operating systems typically use 1,024-based binary units, while advertised drive capacities often use 1,000-based decimal units — this mismatch is the most common source of "missing" storage space confusion.
Frequently asked questions
How many MB are in a GB?
Using the binary convention this calculator applies, 1 GB equals 1,024 MB.
Why does my hard drive show less space than advertised?
Manufacturers typically advertise capacity using 1,000-based decimal units, while your operating system reports free space using 1,024-based binary units — the same physical storage produces a smaller-looking number under the binary convention.
Is 1 TB always exactly 1,024 GB?
Under the binary convention used here, yes. Under the decimal convention sometimes used in marketing, 1 TB would be defined as 1,000 GB instead — always check which convention a given context is using.