NCode.Base64Url 2.0.1

Prefix Reserved

dotnet add package NCode.Base64Url --version 2.0.1

NuGet\Install-Package NCode.Base64Url -Version 2.0.1

This command is intended to be used within the Package Manager Console in Visual Studio, as it uses the NuGet module's version of Install-Package.

<PackageReference Include="NCode.Base64Url" Version="2.0.1" />

For projects that support PackageReference, copy this XML node into the project file to reference the package.

<PackageVersion Include="NCode.Base64Url" Version="2.0.1" />
                    

                            Directory.Packages.props

<PackageReference Include="NCode.Base64Url" />
                    

                            Project file

For projects that support Central Package Management (CPM), copy this XML node into the solution Directory.Packages.props file to version the package.

paket add NCode.Base64Url --version 2.0.1

The NuGet Team does not provide support for this client. Please contact its maintainers for support.

#r "nuget: NCode.Base64Url, 2.0.1"

#r directive can be used in F# Interactive and Polyglot Notebooks. Copy this into the interactive tool or source code of the script to reference the package.

#:package NCode.Base64Url@2.0.1

#:package directive can be used in C# file-based apps starting in .NET 10 preview 4. Copy this into a .cs file before any lines of code to reference the package.

#addin nuget:?package=NCode.Base64Url&version=2.0.1
                    

                            Install as a Cake Addin

#tool nuget:?package=NCode.Base64Url&version=2.0.1
                    

                            Install as a Cake Tool

The NuGet Team does not provide support for this client. Please contact its maintainers for support.

NCode.Base64Url

A high-performance .NET library for encoding and decoding base64url data as defined in RFC 4648 Section 5. Built with modern memory-efficient APIs including Span<T>, ReadOnlySequence<T>, and IBufferWriter<T>.

Features

URL-Safe Encoding — Uses - and _ instead of + and /, making encoded data safe for URLs, filenames, and identifiers
No Padding — Omits trailing = padding characters (decoder accepts both padded and unpadded input)
Zero-Allocation Options — TryEncode/TryDecode methods write directly to caller-provided buffers
Streaming Support — Full support for ReadOnlySequence<T> for processing fragmented/pipelined data
Buffer Writer Integration — Direct output to IBufferWriter<T> for high-throughput scenarios
High Performance — Optimized with unsafe code, lookup tables, and aggressive inlining

Installation

dotnet add package NCode.Base64Url

Quick Start

using NCode.Encoders;

// Encoding
byte[] data = { 0x48, 0x65, 0x6C, 0x6C, 0x6F }; // "Hello" in ASCII
string encoded = Base64Url.Encode(data);         // Returns "SGVsbG8"

// Decoding
byte[] decoded = Base64Url.Decode("SGVsbG8");    // Returns original bytes

API Summary

Encoding Methods

Method	Description
`GetCharCountForEncode(int)`	Calculates the output character count for a given byte count
`Encode(ReadOnlySpan<byte>)`	Encodes bytes to a base64url string
`Encode(ReadOnlySequence<byte>)`	Encodes a byte sequence to a base64url string
`Encode(ReadOnlySpan<byte>, IBufferWriter<char>)`	Encodes bytes directly to a buffer writer
`Encode(ReadOnlySequence<byte>, IBufferWriter<char>)`	Encodes a byte sequence directly to a buffer writer
`TryEncode(ReadOnlySpan<byte>, Span<char>, out int)`	Attempts to encode bytes to a provided character buffer
`TryEncode(ReadOnlySequence<byte>, Span<char>, out int)`	Attempts to encode a byte sequence to a provided character buffer

Decoding Methods

Method	Description
`GetByteCountForDecode(int)`	Calculates the output byte count for a given character count
`Decode(ReadOnlySpan<char>)`	Decodes a base64url string to a byte array
`Decode(ReadOnlySpan<char>, IBufferWriter<byte>)`	Decodes a base64url string directly to a buffer writer
`Decode(ReadOnlySequence<char>, IBufferWriter<byte>)`	Decodes a character sequence directly to a buffer writer
`TryDecode(ReadOnlySpan<char>, Span<byte>, out int)`	Attempts to decode a base64url string to a provided byte buffer
`TryDecode(ReadOnlySequence<char>, Span<byte>, out int)`	Attempts to decode a character sequence to a provided byte buffer

Advanced Usage

Zero-Allocation Encoding

byte[] data = GetData();
int charCount = Base64Url.GetCharCountForEncode(data.Length);
Span<char> buffer = stackalloc char[charCount];

if (Base64Url.TryEncode(data, buffer, out int charsWritten))
{
    // Use buffer[..charsWritten]
}

Zero-Allocation Decoding

ReadOnlySpan<char> encoded = "SGVsbG8";
int byteCount = Base64Url.GetByteCountForDecode(encoded.Length);
Span<byte> buffer = stackalloc byte[byteCount];

if (Base64Url.TryDecode(encoded, buffer, out int bytesWritten))
{
    // Use buffer[..bytesWritten]
}

Using with IBufferWriter

var writer = new ArrayBufferWriter<char>();
int charsWritten = Base64Url.Encode(data, writer);

Target Frameworks

.NET 8.0
.NET 10.0

Release Notes

Version	Changes
v1.0.0	Initial release
v1.1.0	Added support for `ReadOnlySequence<T>`
v1.1.1	Added sequence overloads without buffer writer
v1.1.2	Optimized single-segment sequence handling
v2.0.0	Target .NET 8.0+ only
v2.0.1	Updates to xmldoc and readme

License

Licensed under the Apache License, Version 2.0.

Product	Compatible and additional computed target framework versions.
.NET	net8.0 is compatible. net8.0-android was computed. net8.0-browser was computed. net8.0-ios was computed. net8.0-maccatalyst was computed. net8.0-macos was computed. net8.0-tvos was computed. net8.0-windows was computed. net9.0 was computed. net9.0-android was computed. net9.0-browser was computed. net9.0-ios was computed. net9.0-maccatalyst was computed. net9.0-macos was computed. net9.0-tvos was computed. net9.0-windows was computed. net10.0 is compatible. net10.0-android was computed. net10.0-browser was computed. net10.0-ios was computed. net10.0-maccatalyst was computed. net10.0-macos was computed. net10.0-tvos was computed. net10.0-windows was computed.

Product

.NET

Compatible target framework(s)

Included target framework(s) (in package)

Learn more about Target Frameworks and .NET Standard.

net10.0
- No dependencies.
net8.0
- No dependencies.

NuGet packages

This package is not used by any NuGet packages.

GitHub repositories

This package is not used by any popular GitHub repositories.

Version	Downloads	Last Updated
2.0.1	89	1/17/2026
2.0.0	93	1/11/2026
1.1.2	449	7/30/2023
1.1.1	258	7/28/2023
1.1.0	251	7/28/2023
1.0.0	268	7/16/2023
0.0.4	288	7/16/2023
0.0.3	259	7/16/2023
0.0.2	266	7/15/2023

Built on 2026-01-17 17:14:43Z