What is the difference between MB and MiB?

MB (megabyte) uses the SI definition: 1 MB = 1,000,000 bytes. MiB (mebibyte) uses the binary definition: 1 MiB = 1,048,576 bytes. Operating systems often mix both conventions.

Why does my 1 TB hard drive show less than 1 TB on my computer?

Drive manufacturers use SI TB (10^12 bytes), but operating systems often report in binary GiB, making the drive appear smaller. A 1 TB drive holds approximately 931 GiB.

Is my data sent to a server?

No. All conversions are pure JavaScript calculations running in your browser.

Does the tool support bits as well as bytes?

Yes. The tool includes bits, kilobits, megabits, and gigabits, useful for network speed conversions.

Byte converter

Byte converter is a browser-based digital storage calculator that shows all unit equivalents, bytes, KB, MB, GB, TB, PB, simultaneously. Toggle between decimal SI and binary IEC standards to see the difference between how manufacturers and operating systems count storage.

Standard:

UNIT	VALUE
B	1,000,000
KB	1,000
MB← input	1
GB	0.001
TB	< 0.001
PB	< 0.001

Decimal (SI): 1 KB = 1,000 B · 1 MB = 1,000,000 B · used by storage manufacturers

Dedicated pages

Direct links for common storage conversions.

MB to GB converter

Convert megabytes to gigabytes instantly. Supports both decimal (1 GB = 1000 MB) and binary (1 GiB = 1024 MiB) standards. Free, in-browser.

Bytes to KB converter

Convert bytes to kilobytes (KB) or kibibytes (KiB) instantly. See all storage units at once, bytes, KB, MB, GB and more. Free, in-browser.

File size converter

Convert file sizes between bytes, KB, MB, GB, TB and more. Supports both decimal (SI) and binary (IEC) units. Free, instant, in-browser.

How to convert byte units

Enter a value in the input field.
Select the source unit, bytes, KB, MB, GB, TB, or their binary equivalents.
All other units are displayed simultaneously in the results table.
Toggle between decimal (SI) and binary (IEC) standards using the switch.

Common uses

Converting MB to GB when comparing storage capacities
Understanding file sizes in different units for disk space planning, use unit converter for other measurement categories like length or weight
Converting between SI units (KB = 1000 B) and binary units (KiB = 1024 B). Use the percentage calculator to find how much smaller a compressed file is

Technical specification

Algorithm or formula: Multiplication by base unit factors. SI (decimal) uses powers of 1,000; IEC (binary) uses powers of 1,024. Bits are converted via ×8 / ÷8.
Browser API or library: Pure JavaScript arithmetic. No external library.
Input limits: JavaScript Number range (up to 2^53 safe integer). Very large values lose precision beyond that limit.
Output: All units (B, KB/KiB, MB/MiB, GB/GiB, TB/TiB, PB/PiB, plus bit equivalents) displayed simultaneously, copyable per row.
Known limitations: No support for sub-bit units. Mixed-base inputs (e.g. "1.5 KB") must be entered as plain numbers in one unit at a time.

Frequently asked questions

What is the difference between MB and MiB?: MB (megabyte) uses the SI definition: 1 MB = 1,000,000 bytes. MiB (mebibyte) uses the binary definition: 1 MiB = 1,048,576 bytes. Operating systems often mix both conventions.
Why does my 1 TB hard drive show less than 1 TB on my computer?: Drive manufacturers use SI TB (10^12 bytes), but operating systems often report in binary GiB, making the drive appear smaller. A 1 TB drive holds approximately 931 GiB.
Is my data sent to a server?: No. All conversions are pure JavaScript calculations running in your browser.
Does the tool support bits as well as bytes?: Yes. The tool includes bits, kilobits, megabits, and gigabits, useful for network speed conversions.

Reviewed and tested May 25, 2026.