How many MB are in a GB?

1,000 MB in a decimal gigabyte, or 1,024 MiB in a binary gibibyte.

Why does my 1 TB drive show less space?

Drive makers count 1 TB as 10¹² bytes. Some operating systems report in binary units, where that is about 931 GiB.

What is the difference between MB and MiB?

MB is 1,000,000 bytes. MiB is 1,048,576 bytes, or 1,024².

Data Storage Converter

Convert bits, bytes, KB, MB, GB, TB and the binary units KiB, MiB, GiB and TiB.

Updated September 19, 2026Checked by the editorial team

Value

From

Gigabytes to Megabytes

1,000 MB

1 GB = 1,000 MB

Decimal places

Show 1 GB in every unit

Unit	Value
Bits	8,000,000,000 bit
Bytes	1,000,000,000 B
Kilobytes (1,000 B)	1,000,000 KB
Megabytes (10⁶ B)	1,000 MB
Terabytes (10¹² B)	0.001 TB
Petabytes (10¹⁵ B)	0.000001 PB
Kibibytes (1,024 B)	976,562.5 KiB
Mebibytes (1,024² B)	953.674316 MiB
Gibibytes (1,024³ B)	0.931323 GiB
Tebibytes (1,024⁴ B)	0.000909 TiB

Convert data sizes between bits, bytes and the larger units. The list includes both the decimal units (KB, MB, GB, TB, where each step is 1,000) and the binary units (KiB, MiB, GiB, TiB, where each step is 1,024).

That difference is why a 1 TB drive appears as roughly 931 GB in some operating systems: the drive maker counts in thousands, and the software counts in units of 1,024.

How data storage converter works

Everything is converted through bytes. A byte is 8 bits. Decimal prefixes use powers of 1,000 and binary prefixes use powers of 1,024. Pick the family your source uses.

Network speeds are usually quoted in bits per second, and file sizes in bytes, so divide by 8 when comparing them.

The formula

1 KB = 1,000 B   ·   1 MB = 1,000 KB   ·   1 GB = 1,000 MB   ·   1 TB = 1,000 GB
1 KiB = 1,024 B   ·   1 MiB = 1,024 KiB   ·   1 GiB = 1,024 MiB   ·   1 TiB = 1,024 GiB
1 byte = 8 bits

Worked example: a drive and a download

A 1 TB drive holds 1,000,000,000,000 bytes, which is 931.3 GiB.

A 4.7 GB file over a 100 megabit per second connection is 4.7 × 8,000 ÷ 100 = 376 seconds at best, about 6 minutes 16 seconds.

Quick reference

From	To
1 GB	1,000 MB (0.931323 GiB)
1 GiB	1,024 MiB (1.073742 GB)
1 TB	1,000 GB (0.909495 TiB)
1 TiB	1,024 GiB (1.099512 TB)
1 MB	0.953674 MiB
1 byte	8 bits

When to use this converter

Checking whether a file will fit on a drive or attachment limit.
Understanding why advertised storage differs from what your computer reports.
Estimating download times from file size and connection speed.

Common mistakes to avoid

Mixing MB and Mb. A capital B is bytes and a lowercase b is bits.
Assuming KB always means 1,024 bytes. Some software still uses that, but the standard prefix means 1,000.
Ignoring protocol overhead when estimating download times. Real transfers are somewhat slower than the line rate.

Frequently asked questions

How many MB are in a GB?: 1,000 MB in a decimal gigabyte, or 1,024 MiB in a binary gibibyte.
Why does my 1 TB drive show less space?: Drive makers count 1 TB as 10¹² bytes. Some operating systems report in binary units, where that is about 931 GiB.
What is the difference between MB and MiB?: MB is 1,000,000 bytes. MiB is 1,048,576 bytes, or 1,024².
How many bits are in a byte?: Eight.

Learn more

Results are for information only and are not financial, legal or medical advice. The calculation logic is covered by automated tests, and examples on this page are worked out and re-checked before publishing. Spotted a mistake? Tell us.