What's the difference between KB and KiB?

KB is 1000 bytes under the decimal (SI) convention this tool uses, while KiB is 1024 bytes under the binary (IEC) convention; the same file size shows a slightly smaller number in KB than in KiB.

Why does my file manager show a different size than the download page?

The download page likely advertises size in decimal units (1 MB = 1,000,000 bytes) while your operating system's file manager reports the same bytes in binary units (1 MiB = 1,048,576 bytes), which this tool converts between directly.

How do I convert megabits to megabytes?

Set the From unit to Mbit and enter your value; the Decimal column's MB row shows the byte equivalent, since network speeds are conventionally measured in bits while file sizes are measured in bytes, an 8x difference.

Does this tool round the converted values?

Displayed numbers are formatted to a readable number of decimal places and trimmed of trailing zeros, switching to exponential notation only for extremely large or small results, but the underlying conversion itself is exact floating-point math.

Data Size Converter

Convert between bytes, KB/MB/GB/TB, binary KiB/MiB/GiB and bits, locally.

Local, Runs entirely in your browser, your data never leaves your device.

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Convert bytes to KB, KiB, Mbit and back in one pass

Storage and bandwidth are advertised in decimal units, where 1 KB is 1000 bytes, but operating systems and RAM report binary units, where 1 KiB is 1024 bytes, and the gap between the two grows at every step up. Enter a value and a source unit and this tool converts it into bits, every decimal size up to petabytes and every binary size up to pebibytes at the same time, so you can see exactly how a number changes depending on which convention produced it.

How to use the Data Size Converter

Enter a numeric value in the Value field.
Pick the unit that value is currently in from the From unit dropdown.
Read the "Best fit" line for the value expressed in its most natural binary and decimal unit.
Scan the Bits, Decimal and Binary columns for the same value in every other unit.
Hover a row and click the copy icon to grab that converted number.

Decimal units (KB, MB, GB, TB, PB) use base 1000, matching how drive manufacturers and network speeds are marketed; binary units (KiB, MiB, GiB, TiB, PiB) use base 1024, matching how most operating systems report file and memory sizes.

Bit units (bit, Kbit, Mbit, Gbit) are decimal-based and divided by 8 relative to their byte equivalents, which is the convention used for network throughput, so 8 Mbit equals 1 MB, not 1 MiB.

Frequently asked questions

What's the difference between KB and KiB?: KB is 1000 bytes under the decimal (SI) convention this tool uses, while KiB is 1024 bytes under the binary (IEC) convention; the same file size shows a slightly smaller number in KB than in KiB.
Why does my file manager show a different size than the download page?: The download page likely advertises size in decimal units (1 MB = 1,000,000 bytes) while your operating system's file manager reports the same bytes in binary units (1 MiB = 1,048,576 bytes), which this tool converts between directly.
How do I convert megabits to megabytes?: Set the From unit to Mbit and enter your value; the Decimal column's MB row shows the byte equivalent, since network speeds are conventionally measured in bits while file sizes are measured in bytes, an 8x difference.
Does this tool round the converted values?: Displayed numbers are formatted to a readable number of decimal places and trimmed of trailing zeros, switching to exponential notation only for extremely large or small results, but the underlying conversion itself is exact floating-point math.