What is megabyte (decimal)?

A megabyte in the decimal system is a data unit equal to 1,000 kilobytes. It is commonly used by storage manufacturers, internet service providers, and operating systems to express file sizes and storage capacities.

Real-world uses

Megabytes are the everyday unit for typical file sizes: photos (2–10 MB), MP3 songs (3–10 MB), mobile app downloads (10–100 MB), and email attachments. Mobile data plans are often described in megabytes or gigabytes. A minute of compressed video at 720p is roughly 40–80 MB.

History

The megabyte became a practical everyday unit in the 1980s as personal computers began shipping with hard drives in the megabyte range. Floppy disks (1.44 MB), early hard drives (10–40 MB), and CD-ROMs (650 MB) all popularised the unit during this era.

Common mistakes

The same decimal vs. binary ambiguity as kilobytes applies: 1 MB = 1,000,000 bytes (SI) vs. 1 MB = 1,048,576 bytes (legacy binary). Hard drive manufacturers use the decimal definition, so a "500 MB" drive shows slightly less in an OS that uses binary counting. The binary equivalent is the mebibyte (MiB).

What is byte?

A byte is a fundamental unit of digital information, typically comprising 8 bits. It is the standard unit for measuring file size, storage capacity, and data transfer quantities in computing.

Real-world uses

The byte is the fundamental unit of digital information. File sizes, RAM capacity, hard drive storage, and network data quotas are all measured in bytes and their multiples. A byte is 8 bits and can represent 256 distinct values. Text encoding stores approximately 1 byte per ASCII character.

History

The term "byte" was coined by Werner Buchholz in 1956 while working at IBM on the Stretch computer. He defined it as a group of bits processed together. The 8-bit byte became standard with IBM System/360 in 1964 and has remained the universal digital unit since.

Common mistakes

Confusing bytes (B) with bits (b) — internet speed is often quoted in megabits per second (Mbps), while file sizes are in megabytes (MB). Downloading a 10 MB file at 10 Mbps takes about 8 seconds because 10 MB = 80 Mb.

When is this conversion used?

Operating systems and storage manufacturers use different base systems (binary vs decimal), which is why a '1 TB' drive shows less than 1 TB in your file manager. Understanding this conversion prevents confusion about available storage.

Worked examples

1 megabyte (decimal) = 1,000,000 byte

1 byte = 1 byte

How to convert megabyte (decimal) to byte

To convert megabyte (decimal) to byte, multiply the value by 1,000,000.

To convert byte back to megabyte (decimal), multiply by 0.000001.

Measurement standards

The International Electrotechnical Commission (IEC 80000-13) defines binary prefixes: 1 KiB = 1,024 bytes, 1 MiB = 1,048,576 bytes. The SI decimal prefixes (kB = 1,000 bytes, MB = 1,000,000 bytes) apply to data units as they do to all SI quantities.

Did you know?

By 2025, the global datasphere is estimated to reach 181 zettabytes — roughly 181 trillion gigabytes. If stored on standard Blu-ray discs, the stack would reach from Earth to Mars and back over 20 times.

Quick reference: megabyte (decimal) to byte

megabyte (decimal)byte
0.1100,000
0.5500,000
11,000,000
22,000,000
55,000,000
1010,000,000
2525,000,000
5050,000,000
100100,000,000
250250,000,000
500500,000,000
1,0001.000000e+09

Common values

megabyte (decimal)byte
A text email0.005 megabyte (decimal)5,000 byte
An MP3 song (4 min)4 megabyte (decimal)4,000,000 byte
A smartphone photo5 megabyte (decimal)5,000,000 byte
An HD movie5,000 megabyte (decimal)5.000000e+09 byte
A full hard drive1,000,000 megabyte (decimal)1.000000e+12 byte