fileSizeFormat

Returns the given file size (in bytes) as a human-readable string.

Parameters

Name	Type	Required	Default
bytes	numberintfloat	●	–
Converts it to a human-friendly string via the bytes provided here.
decimalsnamedkeyword	numberint	–	2
Specifies the number of decimal places to represent.
ceilnamedkeyword	booleanbool	–	falseFalse
If this value is trueTrue, the decimal point is removed and the number is rounded up.
optionsnamedkeyword	FileSizeOptions	–	–
See the table below. JavaScript takes these as a fourth object argument, after decimals and ceil.See the table below.

namedThese parameters are passed as named parameters.

keywordThese parameters are passed as keyword arguments, or as a single dict in their place.

FileSizeOptions

Name	Type	Required	Default
standard	'jedec' | 'iec' | 'si'	–	'jedec'
Which divisor to scale by and which unit names to write. See the table below.
unitDisplay	'short' | 'long'	–	'short'
Writes the unit as an abbreviation (MB) or as a whole word (Megabytes). The long form takes the singular when the rounded number is one.

Leaving both options out returns exactly the string this function has always returned.

Standards

standard	Divisor	Units	Example for 1000000
jedec	1024	KB, MB, GB	976.56 KB
iec	1024	KiB, MiB, GiB	976.56 KiB
si	1000	kB, MB, GB	1 MB

jedec is the default because it is what this function has always done: it divides by 1024 and writes KB. iec divides by the same 1024 and writes the prefix that actually means 1024, and si is the decimal one that disk manufacturers quote. Pick iec or si when the number and the unit have to agree.

The unit at exponent zero carries no prefix, so it is Bytes under all three.

Returns

string

String

str

Examples

fileSizeFormat(1000000); // '976.56 KB'
fileSizeFormat(100000000, 3); // '95.367 MB'
fileSizeFormat(100000000, 0, true); // '96 MB'

fileSizeFormat(1000000, 2, false, { standard: 'iec' }); // '976.56 KiB'
fileSizeFormat(1000000, 2, false, { standard: 'si' }); // '1 MB'
fileSizeFormat(1048576, 2, false, { unitDisplay: 'long' }); // '1 Megabyte'
fileSizeFormat(1234567, 2, false, { unitDisplay: 'long' }); // '1.18 Megabytes'

fileSizeFormat(1000000); // '976.56 KB'
fileSizeFormat(100000000, decimals: 3); // '95.367 MB'
fileSizeFormat(100000000, ceil: true); // '96 MB'

fileSizeFormat(1000000, standard: 'iec'); // '976.56 KiB'
fileSizeFormat(1000000, standard: 'si'); // '1 MB'
fileSizeFormat(1048576, unitDisplay: 'long'); // '1 Megabyte'
fileSizeFormat(1234567, unitDisplay: 'long'); // '1.18 Megabytes'

fileSizeFormat(1000000)  # '976.56 KB'
fileSizeFormat(100000000, 3)  # '95.367 MB'
fileSizeFormat(100000000, 0, True)  # '96 MB'

fileSizeFormat(1000000, standard='iec')  # '976.56 KiB'
fileSizeFormat(1000000, standard='si')  # '1 MB'
fileSizeFormat(1048576, unitDisplay='long')  # '1 Megabyte'
fileSizeFormat(1234567, unitDisplay='long')  # '1.18 Megabytes'

Writing the size in another language

The unit names above are English, and this function does not translate them. To render a size in the reader's language, take the number and the unit apart with fileSizeParts and hand them to a formatter that knows the locale.