Data Storage Converter
Using SI decimal prefixes: 1 KB = 1,000 B, 1 MB = 1,000 KB.
SI vs Binary Prefixes
This converter uses SI (decimal) units where 1 KB = 1,000 bytes. Storage manufacturers use this system. Operating systems historically used binary units (1 KiB = 1,024 bytes), which is why a "500 GB" hard drive shows as ~465 GB in Windows.
Common Reference Points
- A typical MP3 song: ~3–5 MB
- A HD photo from a smartphone: ~3–10 MB
- A 4K movie: ~60–100 GB
- A standard DVD: 4.7 GB
- Common SSD sizes: 256 GB, 512 GB, 1 TB, 2 TB
Frequently Asked Questions
Why does my hard drive show less space than advertised?
Drive manufacturers market capacity using decimal (SI) units where 1 GB = 1,000,000,000 bytes. Your OS reports space in binary units where 1 GB = 1,073,741,824 bytes. A 1 TB drive has 1,000,000,000,000 bytes, which the OS shows as roughly 931 GiB.
How many MB in a GB?
Using SI units: exactly 1,000 MB. Using binary units: 1,024 MiB. Storage devices and internet speeds use 1,000; RAM and older OS displays use 1,024.
What is the difference between GB and GiB?
GB (gigabyte) uses the SI decimal definition: 1 GB = 1,000,000,000 bytes. GiB (gibibyte) uses the binary definition: 1 GiB = 1,073,741,824 bytes. The difference is about 7.4%. Storage manufacturers advertise in GB; operating systems historically reported in GiB while labeling them GB, which is the root cause of the "missing space" confusion.
How many GB is a terabyte?
1 terabyte (TB) equals 1,000 gigabytes in SI units — the standard used by hard drive and SSD manufacturers. In binary units, 1 tebibyte (TiB) equals 1,024 gibibytes. A "1 TB" drive contains exactly 1,000,000,000,000 bytes, which your operating system may display as roughly 931 GB.