Blake3.NET [](https://github.com/xoofx/Blake3.NET/actions/workflows/managed.yml) [](https://github.com/xoofx/Blake3.NET/actions/workflows/native.yml) [](https://www.nuget.org/packages/Blake3/)

December 25, 2025 · View on GitHub

Blake3.NET is a fast managed wrapper around the SIMD Rust implementations of the BLAKE3 cryptographic hash function.

The current native version of BLAKE3 used by Blake3.NET is 1.8.2

Features

Compatible with .NET8.0+.
Fast interop with Span friendly API.
API similar to the Blake3 Rust API.
CPU SIMD Hardware accelerated with dynamic CPU feature detection.
- Multiple platforms supported.
Incremental update API via Hasher.
Support for multi-threading hashing via Hasher.UpdateWithJoin.

Usage

Hash a buffer directly:

var hash = Blake3.Hasher.Hash(Encoding.UTF8.GetBytes("BLAKE3"));
Console.WriteLine(hash);
// Prints f890484173e516bfd935ef3d22b912dc9738de38743993cfedf2c9473b3216a4

Or use the Hasher struct for incremental updates:

// Hasher is a disposable struct!
using var hasher = Blake3.Hasher.New();
hasher.Update(Encoding.UTF8.GetBytes("BLAKE3"));
var hash = hasher.Finalize();

Or seek in the output "stream" to any position:

using var hasher = Blake3.Hasher.New();
hasher.Update(Encoding.UTF8.GetBytes("BLAKE3"));
var hashAtPosition = new byte[1024];
var hash = hasher.Finalize(4242, hashAtPosition);

Or hash a stream on the go with Blake3Stream:

using var blake3Stream = new Blake3Stream(new MemoryStream());
blake3Stream.Write(Encoding.UTF8.GetBytes("BLAKE3"));
var hash = blake3Stream.ComputeHash();

Or produce a message authentication code using a 256-bit key:

using var blake3 = Hasher.NewKeyed(macKey);
blake3.UpdateWithJoin(message);
var tag = blake3.Finalize();
byte[] authenticationTag = tag.AsSpan().ToArray();

Or derive a subkey from a master key:

const string context = "[application] [commit timestamp] [purpose]";
using var blake3 = Hasher.NewDeriveKey(Encoding.UTF8.GetBytes(context));
blake3.Update(inputKeyingMaterial);
var derivedKey = blake3.Finalize();
byte[] subkey = derivedKey.AsSpan().ToArray();

Platforms

Blake3.NET is supported on the following platforms:

win-x64, win-x86, win-arm64, win-arm
linux-x64, linux-arm64, linux-arm, linux-musl-x64, linux-musl-arm64
osx-x64, osx-arm64

Benchmarks

The benchmarks are running with BenchmarkDotNet .NET 5.0 and done on multiple different sizes compared with the following implementations:

Blake3.NET (Blake3 Native Version: 0.3.7)
Blake2Fast 2.0.0
System.Security.Cryptography.SHA256 of .NET 5.0

For the 1,000,000 bytes test, Blake3 is using the multi-threading version provided by Blake3 (Hasher.UpdateWithJoin method).

Results

In general, Blake3 is much faster than SHA256 which is depending on whether your CPU supports Intel SHA Extensions.

Blake3 can be from 2x to 10x times faster than SHA256

The multi-threading version can give a significant boost if the data to hash is big enough

Blake3 is usually working best on large input.

Results

The CPU before Intel Ice Lake or AMD Zen don't have the Intel SHA CPU extensions.

In that case, Blake3 is around 5x to 10x times faster than the built-in SHA256.

The following benchmark was ran on an Intel Core i7-4980HQ CPU 2.80GHz (Haswell):

Benchmarks


BenchmarkDotNet=v0.12.1, OS=Windows 10.0.18363.1139 (1909/November2018Update/19H2)
Intel Core i7-4980HQ CPU 2.80GHz (Haswell), 1 CPU, 8 logical and 4 physical cores
.NET Core SDK=5.0.100
  [Host]     : .NET Core 5.0 (CoreCLR 5.0.20.51904, CoreFX 5.0.20.51904), X64 RyuJIT
  DefaultJob : .NET Core 5.0.0 (CoreCLR 5.0.20.51904, CoreFX 5.0.20.51904), X64 RyuJIT

Method	N	Mean	Error	StdDev	Median
Blake3	4	85.06 ns	1.704 ns	2.154 ns	83.55 ns
Blake2Fast	4	138.30 ns	0.755 ns	0.670 ns	138.36 ns
SHA256	4	531.82 ns	0.842 ns	0.788 ns	531.85 ns
Blake3	100	145.12 ns	2.899 ns	4.064 ns	142.56 ns
Blake2Fast	100	153.41 ns	3.057 ns	4.760 ns	150.66 ns
SHA256	100	803.32 ns	11.420 ns	8.916 ns	797.37 ns
Blake3	1000	999.01 ns	19.658 ns	26.908 ns	984.60 ns
Blake2Fast	1000	789.41 ns	15.814 ns	18.825 ns	784.82 ns
SHA256	1000	4,489.81 ns	84.032 ns	78.603 ns	4,525.27 ns
Blake3	10000	4,099.92 ns	49.985 ns	46.756 ns	4,121.94 ns
Blake2Fast	10000	7,593.55 ns	127.193 ns	112.753 ns	7,609.07 ns
SHA256	10000	40,799.82 ns	769.102 ns	1,386.850 ns	41,460.32 ns
Blake3	100000	28,491.58 ns	394.692 ns	369.195 ns	28,498.05 ns
Blake2Fast	100000	78,732.84 ns	648.124 ns	606.255 ns	78,887.56 ns
SHA256	100000	408,581.45 ns	2,359.416 ns	2,207.000 ns	409,059.91 ns
Blake3	1000000	138,481.22 ns	1,300.797 ns	1,216.767 ns	138,460.16 ns
Blake2Fast	1000000	724,092.30 ns	6,995.547 ns	6,543.639 ns	720,115.33 ns
SHA256	1000000	3,699,812.03 ns	37,739.460 ns	35,301.514 ns	3,678,276.17 ns

Results with SHA CPU extensions

If your CPU has Intel SHA CPU extensions, then Blake3 is on average ~2x times faster than SHA256.

The following benchmarks was ran on a AMD Ryzen 9 3900X:

Benchmarks


BenchmarkDotNet=v0.12.1, OS=Windows 10.0.19041.630 (2004/?/20H1)
AMD Ryzen 9 3900X, 1 CPU, 24 logical and 12 physical cores
.NET Core SDK=5.0.100
  [Host]     : .NET Core 5.0 (CoreCLR 5.0.20.51904, CoreFX 5.0.20.51904), X64 RyuJIT
  DefaultJob : .NET Core 5.0.0 (CoreCLR 5.0.20.51904, CoreFX 5.0.20.51904), X64 RyuJIT

Method	N	Mean	Error	StdDev
Blake3	4	77.86 ns	0.332 ns	0.310 ns
Blake2Fast	4	123.57 ns	0.939 ns	0.879 ns
SHA256	4	244.31 ns	1.157 ns	1.082 ns
Blake3	100	125.60 ns	0.497 ns	0.440 ns
Blake2Fast	100	124.48 ns	1.053 ns	0.985 ns
SHA256	100	279.82 ns	1.853 ns	1.734 ns
Blake3	1000	888.90 ns	0.873 ns	0.681 ns
Blake2Fast	1000	790.85 ns	4.364 ns	3.645 ns
SHA256	1000	700.81 ns	2.078 ns	1.842 ns
Blake3	10000	3,508.37 ns	23.411 ns	21.899 ns
Blake2Fast	10000	7,569.91 ns	40.661 ns	38.034 ns
SHA256	10000	4,922.90 ns	14.360 ns	13.432 ns
Blake3	100000	22,109.48 ns	47.699 ns	39.830 ns
Blake2Fast	100000	75,937.97 ns	223.972 ns	209.503 ns
SHA256	100000	48,655.78 ns	102.273 ns	95.666 ns
Blake3	1000000	117,936.94 ns	263.454 ns	246.435 ns
Blake2Fast	1000000	768,752.03 ns	1,836.783 ns	1,718.128 ns
SHA256	1000000	485,944.26 ns	1,326.657 ns	1,240.956 ns

How to Build?

You need to install the .NET 10 SDK or latest Visual Studio 2026. Then from the root folder:

$ dotnet build src -c Release

In order to rebuild the native binaries, you need to run the build scripts from lib/blake3_dotnet

License

This software is released under the BSD-Clause 2 license.

Author

Alexandre Mutel aka xoofx.