File Size Converter
Convert between bytes, KB, MB, GB and TB. See both the decimal values that drive makers use and the binary values your operating system shows.
1 GB = 1,000,000,000 bytes
Decimal (SI, base 1000)
Used by storage makers, network speeds and macOS.
Bits (b)8,000,000,000
Bytes (B)1,000,000,000
Kilobytes (KB)1,000,000
Megabytes (MB)1,000
Gigabytes (GB)1
Terabytes (TB)0.001
Petabytes (PB)0.000001
Binary (IEC, base 1024)
Used by Windows and RAM. Windows labels these as KB, MB, GB.
Kibibytes (KiB)976,562.5
Mebibytes (MiB)953.674316
Gibibytes (GiB)0.931323
Tebibytes (TiB)0.000909
Pebibytes (PiB)0.000000888178
Estimated download time
4G mobile (20 Mbps)6m 40s
Home broadband (50 Mbps)2m 40s
Fiber (300 Mbps)27s
Gigabit (1 Gbps)8s
Why is my 1 TB drive showing 931 GB?
Drive makers count 1 TB as 1,000,000,000,000 bytes. Windows divides by 1024 at every step, so the same drive shows as 931 GiB, which Windows labels "GB".
No space is missing. It is the same number of bytes written in two systems. Internet speeds use bits, so a 100 Mbps line moves about 12.5 MB per second.