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A megabyte (MB) is 1,000,000 bytes in the decimal (SI) system, which equals 1,000 kilobytes or 8,000,000 bits. In the binary system the matching unit is the mebibyte (MiB) = 1,048,576 bytes. Use the calculator below to see any size in bytes, KB, MB, GB, MiB, GiB and megabits.
Megabyte definition
A byte is 8 bits, the unit most computers use to store one character of plain text. The prefix mega means one million, so a megabyte is one million bytes: 1 MB = 106 bytes. Hard-drive makers, phone makers and network providers use this decimal meaning.
Megabyte in other units
| Unit | 1 MB (decimal, SI) | 1 MiB (binary, IEC) |
|---|---|---|
| Bytes | 1,000,000 | 1,048,576 |
| Kilobytes | 1,000 KB | 1,024 KiB (1,048.576 KB) |
| Megabytes | 1 MB | 1.048576 MB |
| Mebibytes | 0.953674 MiB | 1 MiB |
| Gigabytes | 0.001 GB | 0.001048576 GB |
| Bits | 8,000,000 bits | 8,388,608 bits |
| Megabits | 8 Mb | 8.388608 Mb |
The gap is 48,576 bytes per unit: 1,048,576 minus 1,000,000. See MiB to MB and MB vs MiB for the full comparison.
How a megabyte fits in the data-size ladder
| Unit | Bytes | In MB-related terms |
|---|---|---|
| 1 KB | 1,000 bytes | 0.001 MB |
| 1 MB | 1,000,000 bytes | 1,000 KB |
| 1 GB | 1,000,000,000 bytes | 1,000 MB |
| 1 TB | 1,000,000,000,000 bytes | 1,000,000 MB |
Each decimal step is 1,000 times the previous one. For the next steps up, read what is a gigabyte and what is a terabyte.
MB vs Mb: megabytes and megabits
Capital B is bytes, lowercase b is bits. Because 1 byte = 8 bits, 1 MB = 8 Mb, and a connection of 8 Mbps moves 1 MB each second. To convert, divide megabits by 8 to get megabytes. The table shows how long 100 MB takes at common speeds, ignoring overhead:
| Connection speed | Transfer rate | Time to move 100 MB |
|---|---|---|
| 8 Mbps | 1 MB/s | 100 s |
| 16 Mbps | 2 MB/s | 50 s |
| 50 Mbps | 6.25 MB/s | 16 s |
| 100 Mbps | 12.5 MB/s | 8 s |
| 200 Mbps | 25 MB/s | 4 s |
For other speeds use Mbps to MB/s, or check bandwidth transfer time. Bits to bytes covers the 8-to-1 rule.
How much is 1 MB of text?
Plain English text in ASCII uses 1 byte per character, so 1 MB is about 1,000,000 characters. If a page holds about 2,000 characters (an assumed round number; real pages vary), 1 MB is about 500 pages of plain text. Photos, audio and video are stored with compression and metadata, so their sizes do not follow a fixed rule.
Where you see megabytes
- File sizes: documents, images and downloads are listed in KB, MB or GB.
- Upload limits: forms and email systems cap attachments in MB. Convert with the KB to MB or photo resize in KB tools.
- Mobile data: plans and app usage are counted in MB and GB; see MB to GB and GB to MB.
- Download speed: shown in MB/s by browsers and in Mbps by internet providers.
- Memory and storage labels: RAM is counted in binary units (MiB, GiB); drives are sold in decimal units.
To convert any number of bytes into megabytes, use the byte to MB converter or the byte to MB page.
Related: byte to MB, KB to MB, MiB to MB, MB vs MiB, MB to GB, GB to MB, Mbps to MB/s, what is a gigabyte.
FAQ
What is a megabyte?
A megabyte (MB) is a unit of digital data equal to 1,000,000 bytes in the SI (decimal) system. 'Mega' is the SI prefix for one million, and one byte is 8 bits.
How many bytes are in a megabyte?
1 MB is 1,000,000 bytes in the decimal system used by storage makers and networks. In the binary system the unit is the mebibyte (MiB), which is 1,048,576 bytes.
How many KB are in 1 MB?
1 MB is 1,000 KB in the decimal system. In the binary system 1 MiB is 1,024 KiB.
What is the difference between MB and Mb?
MB with a capital B is megabytes; Mb with a lowercase b is megabits. One byte is 8 bits, so 1 MB is 8 Mb. Internet speeds are usually quoted in megabits per second (Mbps).
What is the difference between MB and MiB?
MB is decimal (1,000,000 bytes) and MiB is binary (1,048,576 bytes). A MiB is about 4.86% larger than an MB. Windows often shows MiB values but labels them MB.
How many MB are in a GB?
1 GB is 1,000 MB in the decimal system. In the binary system 1 GiB is 1,024 MiB.
How much text fits in 1 MB?
In plain ASCII text each character takes 1 byte, so 1 MB holds about 1,000,000 characters. If a page holds about 2,000 characters (an assumption, since pages vary), that is roughly 500 pages.