Tools · Data
MB to GB Converter
Free Convert MB to GB, GB to MB, or between any data size — bits, bytes, KB, MB, GB, TB and PB. Switch between binary (1024) and decimal (1000) standards. Calculated instantly in your browser.
Calculated locally in your browser — nothing is sent or stored anywhere.
About MB to GB Converter
Data storage has two competing measurement standards, which is why the same amount of storage can show up as two different numbers. The binary standard treats each step as ×1,024 (so 1 GB = 1,024 MB), and is what Windows, macOS, and Linux typically use when reporting file and folder sizes. The decimal standard treats each step as ×1,000 (so 1 GB = 1,000 MB), and is what storage manufacturers use on packaging for drives, SSDs, and memory cards.
This mismatch is the reason a “1 TB” drive shows up as roughly 931 GB in your file explorer — no storage is missing, it’s just being counted with a different ruler. To be precise about which one you mean, the International Electrotechnical Commission defines binary units with an “i” — KiB, MiB, GiB, TiB — while KB, MB, GB, TB technically refer to the decimal standard, even though they’re often used loosely for either.
Use the standard toggle above to match whichever system your comparison needs — binary for file sizes and memory, decimal for network speeds, marketed drive capacity, or SI-consistent contexts.
How many MB are in a GB?
Using the binary standard (the one most operating systems use for file sizes), 1 GB equals 1,024 MB. Using the decimal standard (the one storage manufacturers use), 1 GB equals 1,000 MB.
Why do my files show a different size than what I bought?
Storage manufacturers advertise capacity using decimal units (1 GB = 1,000,000,000 bytes), while operating systems often display size using binary units (1 GiB = 1,073,741,824 bytes). A 1TB drive can therefore show as roughly 931 GB in your file explorer, even though no storage is missing.
What is the difference between MB and MiB?
MB (megabyte) technically means 1,000,000 bytes under the decimal standard, while MiB (mebibyte) unambiguously means 1,048,576 bytes under the binary standard. In everyday use, “MB” is often used loosely to mean either, which is the root of most storage-size confusion.