Convert between bytes, KB, MB, GB, TB and more — in binary (1024) or decimal (1000) mode.
This File Size Converter turns any digital storage value into every other unit at once — bytes, kilobytes, megabytes, gigabytes, terabytes, petabytes, bits, and their binary counterparts — in both decimal (base 1000) and binary (base 1024) modes side by side.
Storage units are confusing because two different conventions share almost the same names. Decimal units (KB, MB, GB, TB) are powers of 1000 and are used by drive manufacturers, network speeds, and most marketing. Binary units (KiB, MiB, GiB, TiB) are powers of 1024 and are what most operating systems actually count, even when they label the result "MB" or "GB". That gap is why a drive sold as 1 TB shows up as roughly 931 GiB on your computer. This tool keeps both systems visible so you never have to guess which one a number is using. Enter a value, pick its unit, and choose Binary, Decimal, or Both to see every equivalent, plus a bits readout and a human-friendly size. People use it to:
Every conversion runs locally in your browser using exact power-of-1000 and power-of-1024 factors, so the numbers are precise and nothing you type is ever uploaded to a server. Click any result row to copy that value straight to your clipboard.
MB is decimal (1 MB = 1,000,000 bytes) used by storage manufacturers. MiB is binary (1 MiB = 1,048,576 bytes) used by operating systems. They differ by ~5% for MB/MiB and grow at higher units.
Drive makers advertise in decimal TB (10^12 bytes). The OS reports it in binary GiB (2^30), so 1 TB ≈ 931 GiB. Both numbers are correct — they just use different units.
A kilobyte (KB) is 1,000 bytes in the decimal system, while a kibibyte (KiB) is 1,024 bytes in the binary system. The same pattern continues for every step: MB and MiB, GB and GiB, TB and TiB. Manufacturers and networks usually quote the decimal units, but operating systems usually count in binary, which is why the two never quite agree.
A byte is 8 bits. File sizes and storage are almost always measured in bytes (the capital B, as in MB or GB), while network and internet speeds are usually measured in bits (the lowercase b, as in Mbps). That eight-to-one ratio is why a 100 Mbps connection downloads at only about 12.5 MB per second. This tool shows the exact bit count for any value in the Quick reference strip.
The size a download is described as often uses decimal units (1 MB = 1,000,000 bytes), but your operating system may report the saved file in binary units (1 MiB = 1,048,576 bytes) while still labelling it "MB". The file is identical in bytes; only the unit convention differs. Compare both modes here to see exactly how the same byte count looks in each system.
It depends on the system. In decimal units, 1 GB is 1,000 MB, since each step multiplies by 1,000. In binary units, 1 GiB is 1,024 MiB. So if someone quotes a 1.5 GB file, that is 1,500 MB decimal or about 1,536 MiB binary. Enter any value here and pick Both mode to see the exact figures in each convention at once.
Yes. All conversion runs in your browser. Nothing is sent to any server.