Data Size Converter
Convert file or storage sizes between decimal (KB, MB, GB) and binary (KiB, MiB, GiB) units instantly.
About the Data Size Converter
This converter handles digital storage sizes across two families of units: the decimal SI units (kilobyte, megabyte, gigabyte, terabyte, each a power of 1000) and the binary IEC units (kibibyte, mebibyte, gibibyte and so on, each a power of 1024). It also converts bits and bytes, where 1 byte equals 8 bits.
How to use it
- Enter the size you know into its field, for example a download listed in MB.
- Read the equivalent in GB, MiB or plain bytes.
- Switch between bit and byte fields when comparing network speeds to file sizes.
This tool is useful for clearing up the confusion behind why a 1 TB drive shows as roughly 931 GiB in an operating system: the drive uses decimal TB while the OS reports binary GiB. Remember that internet speeds are usually quoted in megabits per second, not megabytes, so divide by 8 to estimate download size. The converter runs entirely in your browser and uploads nothing.
Frequently asked questions
What is the difference between MB and MiB?
A megabyte (MB) is 1,000,000 bytes using the decimal SI definition, while a mebibyte (MiB) is 1,048,576 bytes (1024 x 1024). MiB is the binary unit operating systems often use even when they display the label MB.
How many bytes are in a kilobyte?
In decimal terms a kilobyte (KB) is 1000 bytes. In binary terms a kibibyte (KiB) is 1024 bytes. This tool supports both so you can pick the convention you need.
Why does my 1 TB hard drive show as about 931 GB?
Drive makers count 1 TB as 1,000,000,000,000 bytes (decimal), but the operating system measures in binary gibibytes (1024^3 bytes), which works out to roughly 931 GiB for the same drive.
How do I convert megabits per second to megabytes?
Divide by 8, because one byte is eight bits. A 100 Mbps connection transfers up to about 12.5 MB per second.