ByteSize is a utility class that makes byte size representation in code easier by removing ambiguity of the value being represented. ByteSize is to bytes what System.TimeSpan is to time.
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ByteSize is a utility class that makes byte size representation in code easier by removing ambiguity of the value being represented.

ByteSize is to bytes what System.TimeSpan is to time.

Stable nuget


  • Windows: use Visual Studio
  • Mac OS X
    • Install Mono.
      • NOTE: using brew install mono will not install the PCL libraries required to build the PCL compatible DLLs. The PCL libraries can be installed by running the installer downloaded from
    • Run make build in terminal.
  • Linux
    • Install Mono and the reference assemblies (sudo apt-get referenceassemblies-pcl).
    • Run make build in terminal.


ByteSize assumes 1 kilobyte = 1024 bytes. See why here.

Without ByteSize:

static double MaxFileSizeMBs = 1.5;

// I need it in KBs!
var kilobytes = MaxFileSizeMBs * 1024; // 1536

With ByteSize:

static MaxFileSize = ByteSize.FromMegaBytes(1.5);

// I have it in KBs!
MaxFileSize.KiloBytes;  // 1536

ByeSize behaves like any other struct backed by a numerical value.

// Add
var monthlyUsage = ByteSize.FromGigaBytes(10);
var currentUsage = ByteSize.FromMegaBytes(512);
ByteSize total = monthlyUsage + currentUsage;


// Subtract
var delta = total.Subtract(ByteSize.FromKiloBytes(10));
delta = delta - ByteSize.FromGigaBytes(100);
delta = delta.AddMegaBytes(-100);


You can create a ByteSize object from bits, bytes, kilobytes, megabytes, gigabytes, and terabytes.

new ByteSize(1.5);           // Constructor takes in bytes

// Static Constructors
ByteSize.FromBits(10);       // Bits are whole numbers only
ByteSize.FromBytes(1.5);     // Same as constructor


A ByteSize object contains representations in bits, bytes, kilobytes, megabytes, gigabytes, and terabytes.

var maxFileSize = ByteSize.FromKiloBytes(10);

maxFileSize.Bits;      // 81920
maxFileSize.Bytes;     // 10240
maxFileSize.KiloBytes; // 10
maxFileSize.MegaBytes; // 0.009765625
maxFileSize.GigaBytes; // 9.53674316e-6
maxFileSize.TeraBytes; // 9.31322575e-9

A ByteSize object also contains two properties that represent the largest metric prefix symbol and value.

var maxFileSize = ByteSize.FromKiloBytes(10);

maxFileSize.LargestWholeNumberSymbol;  // "KB"
maxFileSize.LargestWholeNumberValue;   // 10

String Representation

All string operations are localized to use the number decimal separator of the culture set in Thread.CurrentThread.CurrentCulture.


ByteSize comes with a handy ToString method that uses the largest metric prefix whose value is greater than or equal to 1.

ByteSize.FromBits(7).ToString();         // 7 b
ByteSize.FromBits(8).ToString();         // 1 B
ByteSize.FromKiloBytes(.5).ToString();   // 512 B
ByteSize.FromKiloBytes(1000).ToString(); // 1000 KB
ByteSize.FromKiloBytes(1024).ToString(); // 1 MB
ByteSize.FromGigabytes(.5).ToString();   // 512 MB
ByteSize.FromGigabytes(1024).ToString(); // 1 TB


The ToString method accepts a single string parameter to format the output. The formatter can contain the symbol of the value to display: b, B, KB, MB, GB, TB. The formatter uses the built in double.ToString method.

The default number format is 0.## which rounds the number to two decimal places and outputs only 0 if the value is 0.

You can include symbol and number formats.

var b = ByteSize.FromKiloBytes(10.505);

// Default number format is 0.##
b.ToString("KB");         // 10.52 KB
b.ToString("MB");         // .01 MB
b.ToString("b");          // 86057 b

// Default symbol is the largest metric prefix value >= 1
b.ToString("#.#");        // 10.5 KB

// All valid values of double.ToString(string format) are acceptable
b.ToString("0.0000");     // 10.5050 KB
b.ToString("000.00");     // 010.51 KB

// You can include number format and symbols
b.ToString("#.#### MB");  // .0103 MB
b.ToString("0.00 GB");    // 0 GB
b.ToString("#.## B");     // 10757.12 B

// ByteSize object of value 0
var zeroBytes = ByteSize.FromKiloBytes(0); 
zeroBytes.ToString();           // 0 b
zeroBytes.ToString("0 kb");     // 0 kb
zeroBytes.ToString("0.## mb");  // 0 mb


ByteSize has a Parse and TryParse method similar to other base classes.

Like other TryParse methods, ByteSize.TryParse returns boolean value indicating whether or not the parsing was successful. If the value is parsed it is output to the out parameter supplied.

ByteSize output;
ByteSize.TryParse("1.5mb", out output);

// Invalid
ByteSize.Parse("1.5 b");   // Can't have partial bits

// Valid
ByteSize.Parse("1.55 kB "); // Spaces are trimmed
ByteSize.Parse("1.55 kb");
ByteSize.Parse("1.55 MB");
ByteSize.Parse("1.55 mB");
ByteSize.Parse("1.55 mb");
ByteSize.Parse("1.55 GB");
ByteSize.Parse("1.55 gB");
ByteSize.Parse("1.55 gb");
ByteSize.Parse("1.55 TB");
ByteSize.Parse("1.55 tB");
ByteSize.Parse("1.55 tb");
ByteSize.Parse("1,55 kb"); // de-DE culture

Author and License

Omar Khudeira (

Copyright (c) 2013-2016 Omar Khudeira. All rights reserved.

Released under MIT License (see LICENSE file).