How many megabytes are in a gigabyte?

  Improve

Standard definition

Officially, there are 1000 (10³) megabytes (MB) in a gigabyte (GB). So 500MB would equal 0.5 GB.

This definition is used in hard drives, portable memory drives (memory cards, USB drives), DVDs, Blu-ray disks, and most measures of performance. Some software (such as Mac OS X and the Linux kernel) uses this definition when displaying file and disk sizes.

MB stands for megabyte. Mb with lowercase b is ambiguous, as it has been used for both "megabyte" and "megabit". Writing megabytes as MB and megabits as Mbit avoids any confusion.
 

Memory manufacturer definition

Another definition is used by memory manufacturers and some software, like Microsoft Windows. They use 1024 (2¹⁰) megabytes per gigabyte, but this is more properly called a gigabinary byte (GiB), sometimes contracted to gibibyte.

Using the non-standard definition:

• 1 megabyte (MB) = 1024 kilobytes (KB)
  
• 1 gigabyte (GB) = 1024 megabytes (MB) or 8192 megabits (Mb)
  

 

Examples:

• 1,000 megabyte (MB) = 1 gigabyte (GB)
• 1,024 mebibyte (MiB) = 1 gibibyte (GiB)
• 1 megabyte = 8 megabits
• mega- = 1,000,000
• giga- = 1,000,000,000
• mebi- = 1,024 × 1,024 = 1,048,576
• gibi- = 1,024 × 1,024 × 1,024 = 1,073,741,824

Note: There are comments associated with this question. See the discussion page to add to the conversation.

This answer is closed to changes. This is done in rare cases when questions are being vandalized or answers have become debates. E-mail reopen @ answers.com (no spaces) if you would like it to be reopened.

First answer by ID3407485140. Last edit by Beepboop. Contributor trust: 70 [recommend contributorrecommended]. Question popularity: 277 [recommend question].