What is the difference between a megabyte (MB) and a mebibyte (MiB)?

A megabyte is 1,000,000 bytes (decimal, 1000-based) and a mebibyte is 1,048,576 bytes (binary, 1024-based). They differ by about 4.9%, and the gap grows at each higher tier. This converter shows both so you can compare them directly.

Why does a 1 TB drive show as roughly 931 GB in my operating system?

The manufacturer counts 1 TB as 1,000,000,000,000 bytes using decimal units, while Windows and many tools display binary units and call the same bytes about 931 GiB (often still labelled 'GB'). No space is missing — it is the 1000 versus 1024 difference.

How do I convert megabits to megabytes?

Divide by 8, because one byte is eight bits. So 100 Mbit is 12.5 MB, and 1 Gbit is 125 MB. Flip the Bytes/Bits toggle to read a value in both denominations at once.

How many bytes are in a gigabyte?

It depends on the definition. A decimal gigabyte (GB) is 1,000,000,000 bytes, while a binary gibibyte (GiB) is 1,073,741,824 bytes. The converter lists both alongside the raw byte count so there is no ambiguity.

Should I use 1000-based (SI) or 1024-based (IEC) units?

Use decimal SI units (KB, MB, GB) for storage marketing, network transfer, and most documentation; use binary IEC units (KiB, MiB, GiB) when a value comes from memory or an operating system's file-size display. The tool shows both so you can match whichever your context expects.

Are the sizes I enter into the converter kept on my device?

Yes. Every conversion is calculated locally in your browser with plain arithmetic, so the numbers and units you type are not uploaded or logged anywhere.

Data Size Converter

Convert a value across bytes, bits, and every decimal (KB, MB, GB) and binary (KiB, MiB, GiB) unit at once, right in your browser. The numbers stay on your device.

The Data Size Converter does every calculation in your browser using plain arithmetic. The values and units you enter stay on your device and are never uploaded to ArrayKit.

Working in binary? Try the Number Base Converter.

About Data Size Converter

The Data Size Converter turns a single value into every storage and bandwidth unit at once, so you can stop guessing whether a gigabyte means 1,000,000,000 or 1,073,741,824 bytes. Enter a number in bytes, KB, MB, GB, TB or PB and the tool lays out the decimal (SI, 1000-based) ladder, the binary (IEC, 1024-based) ladder, and the raw bit and byte counts side by side. A bits-versus-bytes toggle switches the whole board between storage sizes and network throughput, where 8 bits make 1 byte. Each result has a copy button and drops trailing zeros for clean values. Every conversion is plain arithmetic that runs in your browser, so the numbers you type never leave your device.

Features

Shows bytes, bits, and the full KB/MB/GB/TB/PB ladder from one value
Decimal (1000-based, SI) and binary (1024-based, IEC) units side by side
Bits-versus-bytes toggle switches between storage sizes and bandwidth
Always displays raw bit and byte counts so 8-bits-per-byte stays visible
Copy button on every unit, with trailing zeros trimmed for clean numbers
Clearly labels the 1000 vs 1024 distinction that trips up disk-size math
Handles values from a single bit up to petabytes and pebibytes
Runs on plain arithmetic in your browser — the values you enter stay local

How to use the Data Size Converter

Type a value into the field and pick its unit from the dropdown.
Read the equivalent across the decimal, binary, and base rows at once.
Use the Bytes/Bits toggle to switch between storage and bandwidth units.
Click the copy button beside any unit to grab that value on its own.

Example

Input

1500 MB

Output

= 1.5 GB (decimal)
= 1.397 GiB (binary)
= 1,500,000,000 bytes
= 12,000,000,000 bits

1500 MB is exactly 1.5 GB, but only about 1.397 GiB because binary units step by 1024.

Common errors & troubleshooting

Your file manager reports fewer GB than the drive's printed label. — Drive makers count in decimal GB (1000-based) while most operating systems display binary GiB (1024-based). A '1 TB' drive holds 1,000,000,000,000 bytes, which is about 931 GiB — the same bytes, labelled two ways.
A download quoted in Mbps finishes slower than you expected in MB. — Bandwidth is quoted in megabits (Mbit), storage in megabytes (MB). Divide the bit figure by 8: 100 Mbit/s is about 12.5 MB/s. Flip the Bytes/Bits toggle to see both denominations.
MB and MiB look almost equal for small numbers but drift apart later. — They start close (1 MB = 1,000,000 B, 1 MiB = 1,048,576 B — a 4.9% gap) but the gap compounds each tier, reaching about 10% at the tera level. Pick the unit your context actually uses.
The converter shows a value in exponent form like 1e-9. — That happens when a very large unit expresses a tiny quantity, such as one byte measured in petabytes. It is the exact value written compactly, not an error.

Frequently asked questions

What is the difference between a megabyte (MB) and a mebibyte (MiB)?: A megabyte is 1,000,000 bytes (decimal, 1000-based) and a mebibyte is 1,048,576 bytes (binary, 1024-based). They differ by about 4.9%, and the gap grows at each higher tier. This converter shows both so you can compare them directly.
Why does a 1 TB drive show as roughly 931 GB in my operating system?: The manufacturer counts 1 TB as 1,000,000,000,000 bytes using decimal units, while Windows and many tools display binary units and call the same bytes about 931 GiB (often still labelled 'GB'). No space is missing — it is the 1000 versus 1024 difference.
How do I convert megabits to megabytes?: Divide by 8, because one byte is eight bits. So 100 Mbit is 12.5 MB, and 1 Gbit is 125 MB. Flip the Bytes/Bits toggle to read a value in both denominations at once.
How many bytes are in a gigabyte?: It depends on the definition. A decimal gigabyte (GB) is 1,000,000,000 bytes, while a binary gibibyte (GiB) is 1,073,741,824 bytes. The converter lists both alongside the raw byte count so there is no ambiguity.
Should I use 1000-based (SI) or 1024-based (IEC) units?: Use decimal SI units (KB, MB, GB) for storage marketing, network transfer, and most documentation; use binary IEC units (KiB, MiB, GiB) when a value comes from memory or an operating system's file-size display. The tool shows both so you can match whichever your context expects.
Are the sizes I enter into the converter kept on my device?: Yes. Every conversion is calculated locally in your browser with plain arithmetic, so the numbers and units you type are not uploaded or logged anywhere.

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