Data size converter

How much data is that in other units?

Convert between bytes, kilobytes, megabytes, gigabytes, MiB, GiB and bits, with 1,000 and 1,024 kept apart.

Data size

From

Result

1,000 MB

1 gigabyte equals 1,000 megabytes

The other way round: 1 MB = 0.001 GB.
Exact by definition: 1 MB = 1,000,000 B.

In all units

Bits: 8,000,000,000 bit
Bytes: 1,000,000,000 B
Kilobytes: 1,000,000 kB
Megabytes: 1,000 MB
Gigabytes: 1 GB
Terabytes: 0.001 TB
Kibibytes: 976,562.5 KiB
Mebibytes: 953.7 MiB
Gibibytes: 0.9313 GiB
Tebibytes: 0.0009095 TiB
Kilobits: 8,000,000 kbit
Megabits: 8,000 Mbit
Gigabits: 8 Gbit

How to use

Type the data size you want to convert.
Choose the units to convert from and to. Use the swap button to flip them.

GB → GiB

GB	GiB
128	119.2093
256	238.4186
512	476.8372
1,000	931.3226
2,000	1,862.6451
4,000	3,725.2903

How it works

Every unit is converted through bytes. A byte is 8 bits. The prefixes kilo, mega, giga and tera mean powers of 1,000: a gigabyte (GB) is 1,000,000,000 bytes. The binary prefixes kibi, mebi, gibi and tebi mean powers of 1,024: a gibibyte (GiB) is 2³⁰ = 1,073,741,824 bytes. So 1 GB is about 0.9313 GiB.

Drive makers use the 1,000-based units, so a 1 TB disk holds 1,000,000,000,000 bytes. Some operating systems count in 1,024s but still write GB, so the same disk shows about 931 “GB”, which is really 931 GiB. Nothing is missing.

The decimal prefixes come from the BIPM SI Brochure and the binary prefixes from IEC 80000-13, listed by NIST. Bit units (kbit, Mbit, Gbit) are 1,000-based, as network speeds use.

Frequently asked questions

Is a kilobyte 1,000 or 1,024 bytes?

By the standard, a kilobyte (kB) is 1,000 bytes and a kibibyte (KiB) is 1,024 bytes. Older software often used “KB” for 1,024.

Why does my 1 TB drive show 931 GB?

The maker counts 1 TB as 10¹² bytes. The computer divides by 1,024³ and still calls the result GB, giving about 931. It is really 931 GiB.

How many MB are in a GB?

1,000 MB in a gigabyte, and 1,024 MiB in a gibibyte.

How many bits are in a byte?

8 bits. Network speeds are in bits per second, files in bytes, so divide by 8: 100 Mbit is 12.5 MB.

Does this calculate download time?

No. It converts data amounts. Download time also needs a transfer rate, and real transfers include overhead and interruptions.

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