megabytes

IPA/ˈmeɡ.ə.baɪt/
KK[mˈɛɡəbˌaɪts]IPA/ˈmeɡ.ə.baɪt/

megabytes — noun

  • megabytessingular
  • megabytesesplural

1. a unit for measuring computer data that equals 1,048,576 bytes — the way a compu

1.nounB2
Definition

a unit for measuring computer data that equals 1,048,576 bytes — the way a computer naturally counts information by grouping data in multiples of 1,024 (2¹⁰)

Example

Nadia checked her system monitor, and the 4 GB flash drive showed only 3,815 megabytes of free space.

binary calculation in operating systems vs. advertised size

The video file took up 892 megabytes of memory on Kenji's laptop after compression.

Common collocations
  • megabytes of RAM
  • megabytes of memory
  • megabytes of data
  • megabytes of storage
  • binary megabytes
Synonyms
  • mebibyte

    the precise IEC name for 1,048,576 bytes, used in formal technical writing to avoid confusion with the decimal megabyte

  • MiB

    the abbreviation for mebibyte; often seen in Linux and server documentation

Grammar Patterns

[number] + megabytes + of + [data/storage/memory]

Usage Note

Frequently shown in operating system displays, task managers, and system-monitoring tools. A number divisible by 1,024 (such as 2,048 or 4,096) almost certainly represents binary megabytes. The formal IEC term for this exact unit is mebibyte (MiB), but most software continues to label it 'MB'.

Common Mistakes

My 256 GB phone has exactly 256,000 megabytes of space.
My 256 GB phone has about 244,000 binary megabytes available to the OS.
Manufacturers advertise capacity in decimal units (1 GB = 1,000 MB), but operating systems report it in binary megabytes (1 GB = 1,024 MB).

2. a unit for measuring computer data that equals 1,000,000 bytes — the way hard dr

2.nounB2
Definition

a unit for measuring computer data that equals 1,000,000 bytes — the way hard drive, solid-state drive, and flash storage manufacturers describe capacity on product labels and in advertising

Example

The hard drive was advertised at 500 gigabytes, but the operating system showed roughly 465,000 megabytes.

contrast between advertised decimal size and actual binary size

Nellie compared two USB drives on the store shelf; the package claimed 64,000 megabytes on each.

Common collocations
  • decimal megabytes
  • advertised as [number] megabytes
  • [number] megabytes on the label
  • marketed as [number] megabytes
Synonyms
  • marketing megabyte

    an informal way to refer to the decimal megabyte used in product advertising

  • million bytes

    a plain-English explanation of the decimal megabyte amount

Grammar Patterns

advertised / listed / marketed as [number] + megabytes

[number] + megabytes + on the + [label / package / spec sheet]

Usage Note

Commonly seen on product packaging, marketing materials, and spec sheets for hard drives, SSDs, USB flash drives, and memory cards. Because the decimal megabyte is about 4.6% smaller than the binary megabyte, a drive advertised as 500 GB (decimal) shows roughly 465 GB (binary) once connected to a computer — this is normal, not a defect.

Common Mistakes

The 128 GB USB stick is defective — it only shows 119 GB on my computer.
The 128 GB USB stick is working fine; the difference between 128 GB (decimal) and 119 GB (binary) is expected.
This discrepancy is caused by the binary-versus-decimal difference, not a hardware fault.

Word family

Synonym discussion

Sense: noun/1

A megabyte (MB) and a mebibyte (MiB) both describe amounts of digital data, but they differ by roughly 4.6%. The megabyte has two definitions — 1,000,000 bytes (decimal, used by storage manufacturers) or 1,048,576 bytes (binary, used by operating systems) — while a mebibyte is always exactly 1,048,576 bytes. A gigabyte (GB) magnifies this gap: 1 decimal GB = 1,000 MB, but 1 binary GB = 1,024 MB. The byte is simply 8 bits, the basic building block. In everyday speech, people say 'megabyte' for both values, but to avoid confusion in documentation, using 'mebibyte' (MiB) for the binary amount makes the meaning clear. For example, a file that the system shows as 100 MiB is actually 104.9 MB by the decimal measure manufacturers use.

megabyte ↗mebibytegigabytebyte ↗

Common collocations

Nouns

  • megabyte limit
  • megabyte count
  • megabyte size

Phrases

  • megabytes per second
  • megabytes in size
  • measured in megabytes

Prepositions

  • megabytes of

Etymology

GreekEnglish (coined)English

Formed by combining the prefix mega- (from Greek μέγας 'great', used in the metric system to mean one million) with the word byte (coined by IBM computer scientist Werner Buchholz in 1956 as a deliberate respelling of 'bite' to avoid accidental mutation). The term 'megabyte' first appeared in the early 1960s as computer memory capacities grew into the millions of bytes.

First known use

1965

1965, in the meaning defined above