Skip to main content

Look up any data unit and learn exactly what it holds

Open a unit to get its definition, exact byte and bit count, its decimal or binary twin, everyday file-size examples and a converter to every other unit. Start with the basics if bits and bytes are new, or jump straight to the exact unit you're looking for using the filter below.

Bits, Bytes and the Decimal vs Binary Divide

Every piece of digital data is ultimately a sequence of bits — single 0s and 1s. Group eight bits and you get a byte. From there, storage units scale up in one of two systems: decimal (SI), where each step multiplies by 1,000 (KB, MB, GB, TB...), or binary (IEC), where each step multiplies by 1,024 (KiB, MiB, GiB, TiB...). Manufacturers label drive capacity in decimal; operating systems often display it in binary — which is why a "1 TB" drive shows as roughly 931 GB in Windows.

Transfer rates carry a similar split, but along a different axis: bits per second (bps, Mbps, Gbps) is what ISPs and network hardware advertise, while bytes per second (B/s, MB/s, GB/s) is what your download manager reports. Since 1 byte = 8 bits, an advertised "500 Mbps" connection tops out around 62.5 MB/s of actual file-transfer throughput.