Browse free open source C Algorithms and projects below. Use the toggles on the left to filter open source C Algorithms by OS, license, language, programming language, and project status.

  • $300 Free Credits for Your Google Cloud Projects Icon
    $300 Free Credits for Your Google Cloud Projects

    Start building on Google Cloud with $300 in free credits. No commitment, no credit card required until you're ready to scale.

    Launch your next project with $300 in free Google Cloud credits—no strings attached. Test, build, and deploy without risk. Use your credits across the entire Google Cloud platform to find what works best for your needs. After your credits are used, continue with always-free tier services. Only pay when you're ready to scale. Sign up in minutes and start exploring.
    Start Free Trial
  • MongoDB Atlas runs apps anywhere Icon
    MongoDB Atlas runs apps anywhere

    Deploy in 115+ regions with the modern database for every enterprise.

    MongoDB Atlas gives you the freedom to build and run modern applications anywhere—across AWS, Azure, and Google Cloud. With global availability in over 115 regions, Atlas lets you deploy close to your users, meet compliance needs, and scale with confidence across any geography.
    Start Free
  • 1
    Library and command line tools for XZ and LZMA compressed files
    Leader badge
    Downloads: 73,379 This Week
    Last Update:
    See Project
  • 2
    Technical analysis library with indicators like ADX, MACD, RSI, Stochastic, TRIX... includes also candlestick pattern recognition. Useful for trading application developpers using either Excel, .NET, Mono, Java, Perl or C/C++.
    Leader badge
    Downloads: 8,263 This Week
    Last Update:
    See Project
  • 3

    lpsolve

    Mixed Integer Linear Programming (MILP) solver.

    Mixed Integer Linear Programming (MILP) solver lp_solve solves pure linear, (mixed) integer/binary, semi-cont and special ordered sets (SOS) models.lp_solve is written in ANSI C and can be compiled on many different platforms like Linux and WINDOWS This project is moved to github: https://lp-solve.github.io/
    Leader badge
    Downloads: 3,021 This Week
    Last Update:
    See Project
  • 4
    LZ4

    LZ4

    Extremely fast compression algorithm

    LZ4 is lossless compression algorithm, providing compression speed > 500 MB/s per core (>0.15 Bytes/cycle). It features an extremely fast decoder, with speed in multiple GB/s per core (~1 Byte/cycle). A high compression derivative, called LZ4_HC, is available, trading customizable CPU time for compression ratio. LZ4 library is provided as open-source software using a BSD license. This benchmark simulates simple "static content transfer" scenario such as OS Kernel compression or video game's static assets (text/images/tables/scripts/etc) which loading from Flash Memory / HDD / SSD. In this case, compression time is completely ignored. Because only content developers compress the data at once and usually they don't care about its computational cost. But they always care end user's experience a.k.a. "loading time" and bandwidth. Please pay attention to "LZ4HC -9" which is quite faster than other methods.
    Downloads: 249 This Week
    Last Update:
    See Project
  • 99.99% Uptime for MySQL and PostgreSQL Databases Icon
    99.99% Uptime for MySQL and PostgreSQL Databases

    Sub-second maintenance. 2x read/write performance. Built-in vector search for AI apps.

    Cloud SQL Enterprise Plus delivers near-zero downtime with 35 days of point-in-time recovery. Supports MySQL, PostgreSQL, and SQL Server.
    Try Free
  • 5
    RHash
    RHash (Recursive Hasher) is a console utility for computing and verifying hash sums of files. It supports CRC32, CRC32C, MD4, MD5, SHA1, SHA256, SHA512, SHA3, AICH, ED2K, DC++ TTH, BTIH, Tiger, GOST R 34.11-2012, RIPEMD-160, HAS-160, EDON-R, and Whirlpool.
    Leader badge
    Downloads: 988 This Week
    Last Update:
    See Project
  • 6
    Real-ESRGAN ncnn Vulkan

    Real-ESRGAN ncnn Vulkan

    NCNN implementation of Real-ESRGAN

    Real-ESRGAN ncnn Vulkan is an optimized, cross-platform implementation of Real-ESRGAN using the ncnn neural network inference engine and Vulkan for hardware acceleration. Unlike the standard PyTorch-based Real-ESRGAN code, this variant is written in C/C++ and designed to run efficiently on many platforms (including Windows, Linux, and possibly Android) without requiring heavy frameworks like CUDA or Python. It provides command-line tools for upscaling images with selected models, allowing users to specify input/output paths, scaling factors, tile sizes, and model names from a compressed model set, which is particularly helpful for larger images or automated workflows. The Vulkan backend enables fast execution on GPUs from different vendors (Intel/AMD/Nvidia) with broad support, making it suitable for non-Python environments, production systems, or performance-constrained setups.
    Downloads: 108 This Week
    Last Update:
    See Project
  • 7
    Zstandard

    Zstandard

    Zstandard - Fast real-time compression algorithm

    Zstandard is a fast compression algorithm, providing high compression ratios. It also offers a special mode for small data, called dictionary compression. The reference library offers a very wide range of speed / compression trade-off, and is backed by an extremely fast decoder (see benchmarks below). Zstandard library is provided as open source software using a BSD license. Its format is stable and published as IETF RFC 8478. The negative compression levels, specified with --fast=#, offer faster compression and decompression speed in exchange for some loss in compression ratio compared to level 1, as seen in the table above. Zstd can trade compression speed for stronger compression ratios. It is configurable by small increment. Decompression speed is preserved and remain roughly the same at all settings, a property shared by most LZ compression algorithms, such as zlib or lzma.
    Downloads: 89 This Week
    Last Update:
    See Project
  • 8
    libmng -THE reference library for reading, displaying, writing and examining Multiple-Image Network Graphics. MNG is the animation extension to the popular PNG image-format.
    Leader badge
    Downloads: 1,265 This Week
    Last Update:
    See Project
  • 9
    CRC RevEng

    CRC RevEng

    Arbitrary-precision CRC calculator and algorithm finder

    CRC RevEng is a portable, arbitrary-precision CRC calculator and algorithm finder. It calculates CRCs using any of the 113 preset algorithms, or a user-specified algorithm to any width. It calculates reversed CRCs to give the bit pattern that produces a desired forward CRC. CRC RevEng also reverse-engineers any CRC algorithm from sufficient correctly formatted message-CRC pairs and optional known parameters. It comprises powerful input interpretation options. Compliant with Ross Williams' Rocksoft(tm) model of parametrised CRC algorithms.
    Leader badge
    Downloads: 157 This Week
    Last Update:
    See Project
  • $300 Free Credits to Build on Google Cloud Icon
    $300 Free Credits to Build on Google Cloud

    New to Google Cloud? Get $300 in credits to explore Compute Engine, BigQuery, Cloud Run, Gemini Enterprise Agent Platform, and more.

    Start your next project with $300 in free Google Cloud credit. Spin up VMs, run containers, query petabytes in BigQuery, or build agents with Gemini Enterprise Agent Platform. Once your credits are used, keep building with 20+ always-free tier products including Compute Engine, Cloud Storage, GKE, and Cloud Run functions. No commitment required—just sign up and start building.
    Claim $300 Free
  • 10
    xxHash

    xxHash

    Extremely fast non-cryptographic hash algorithm

    xxHash is an extremely fast non-cryptographic hash algorithm, working at RAM speed limit. It is proposed in four flavors (XXH32, XXH64, XXH3_64bits and XXH3_128bits). The latest variant, XXH3, offers improved performance across the board, especially on small data. It successfully completes the SMHasher test suite which evaluates collision, dispersion and randomness qualities of hash functions. Code is highly portable, and hashes are identical across all platforms (little / big endian). Performance on large data is only one part of the picture. Hashing is also very useful in constructions like hash tables and bloom filters. In these use cases, it's frequent to hash a lot of small data (starting at a few bytes). Algorithm's performance can be very different for such scenarios, since parts of the algorithm, such as initialization or finalization, become fixed cost. The impact of branch misprediction also becomes much more present.
    Downloads: 6 This Week
    Last Update:
    See Project
  • 11
    ArpON

    ArpON

    ARP handler inspection

    ArpON (ARP handler inspection) is a Host-based solution that make the ARP standardized protocol secure in order to avoid the Man In The Middle (MITM) attack through the ARP spoofing, ARP cache poisoning or ARP poison routing attack.
    Downloads: 46 This Week
    Last Update:
    See Project
  • 12
    iat is Iso9660 Analyzer Tool, this tool have engine for detect many structure of image file
    Leader badge
    Downloads: 45 This Week
    Last Update:
    See Project
  • 13
    LinAsm

    LinAsm

    Collection of fast and optimized assembly libraries for x86-64 Linux

    LinAsm is collection of very fast and SIMD optimized assembly written libraries for x86-64 Linux. It implements many common and widely used algorithms for array manipulations: searching, sorting, arithmetic and vector operations, unit conversions; fast mathematical and statistic functions; numbers and time converting algorithms; finite impulse response (FIR) digital filters; spectrum analysis algorithms, Fast Hartley transformation; CPU cache friendly functions and extremely fast abstract data types (ADT) such as hash tables b-trees, and much more. LinAsm libraries are written on FASM assembly language. They are stable and have appropriate benchmarks for many units. All libraries are well documented and grouped by their functionality. To get more information about this library, please visit the official web site: http://linasm.sourceforge.net
    Leader badge
    Downloads: 25 This Week
    Last Update:
    See Project
  • 14
    The fstrcmp project provides a shared library for making fuzzy string comparisons, and also provides an fstrcmp command for use in shell scripts.
    Leader badge
    Downloads: 43 This Week
    Last Update:
    See Project
  • 15
    MultiFast

    MultiFast

    Mass String Search and Replace Solution via Aho-Corasick Algorithm

    Multifast provides you with efficient library and tool, to search and manipulate data streams on the fly. It can search for a huge number of strings and replace them in one pass. It contains a tidy and efficient implementation of the Aho-Corasick algorithm as a C library.
    Downloads: 15 This Week
    Last Update:
    See Project
  • 16
    Utah Raster Toolkit

    Utah Raster Toolkit

    The Utah Raster Toolkit 3.0, patchlevel 2

    This is the Utah Raster Toolkit distribution version 3.0 of June, 1990. ~~~ librle.a, image.rle file type support, animation, rletogif, converters, many utilities. RLE format supports a great number of raw inner formats for applications to use, known together as .rle (ie, "stored windowing") ~~~ The Utah Raster toolkit is a collection of programs and C routines for dealing with raster images commonly encountered in computer graphics. It provides the following major functions: * A device and system independent image format for storing images and information about them. Called the RLE format, it uses run length encoding to reduce storage space for most images. * A library of C routines for reading, writing and manipulating images stored in the RLE format. * A collections of programs for manipulating and displaying RLE images. License: says it's "GNU like" in the license.
    Downloads: 25 This Week
    Last Update:
    See Project
  • 17

    Jojos Binary Diff

    Binary Diff and Undiff Utility

    JDIFF is a program that outputs the differences between two binary files, either in binary format or in human readable format (detailed or summarized) and then allows to reconstruct the second file from the first one and the diff-file.
    Leader badge
    Downloads: 6 This Week
    Last Update:
    See Project
  • 18
    basE91 is an advanced method for encoding binary data as ASCII characters. It is similar to UUencode or base64, but is more efficient. The overhead produced by basE91 depends on the input data. It amounts at most to 23% and can range down to 14%.
    Downloads: 20 This Week
    Last Update:
    See Project
  • 19
    This is a hash table, implemented in C, supporting constant-time add/find/remove of C structures. Any structure having a unique, arbitrarily-typed key member can be hashed by adding a UT_hash_handle member to the structure and calling these macros.
    Downloads: 3 This Week
    Last Update:
    See Project
  • 20
    C++ Revenue Management Open Library
    That project (RMOL) aims at giving developers concerned by the Revenue Management arena a library delivering a reference implementation for most of the published algorithms and methods. That library is intended to be used in simulated environment: it does not intend to be used in real world production systems.
    Downloads: 13 This Week
    Last Update:
    See Project
  • 21
    CloudI: A Cloud at the lowest level
    CloudI is an open-source private cloud computing framework for efficient, secure, and internal data processing. CloudI provides scaling for previously unscalable source code with efficient fault-tolerant execution of ATS, C/C++, Erlang/Elixir, Go, Haskell, Java, JavaScript/node.js, OCaml, Perl, PHP, Python, Ruby, or Rust services. The bare essentials for efficient fault-tolerant processing on a cloud!
    Downloads: 12 This Week
    Last Update:
    See Project
  • 22
    McuOnEclipse

    McuOnEclipse

    Releases of McuOnEclipse projects

    Processor Expert components and Eclipse examples and plugins.
    Downloads: 12 This Week
    Last Update:
    See Project
  • 23
    PHPXref is a developers tool, written in Perl, that will cross reference and extract inline documentation from a collection of PHP scripts. It generates simple HTML output suitable for browsing offline.
    Downloads: 4 This Week
    Last Update:
    See Project
  • 24
    EN: Code created to show how is done the calculation of a CRC. It includes many different CRCs to choose from. This software was created to help people understand how is the CRC calculated and be able to see it in a practical way, it is also available to copy and use it for your own project. I hope it helps you. ES: Código creado para mostrar como se realiza el cálculo de un CRC. Con el mismo se incluyen varios CRCs que pueden ser escogidos. Este software se creó con el propósito de ayudar a la gente a entender como se hace el cálculo de un CRC de una manera más práctica y sencilla, también se puede copiar y aprovecharlo para otras aplicaciones. Espero que te sea util.
    Downloads: 3 This Week
    Last Update:
    See Project
  • 25
    minidjvu is a DjVu encoder for black-and-white images.
    Downloads: 3 This Week
    Last Update:
    See Project
  • Previous
  • You're on page 1
  • 2
  • 3
  • 4
  • 5
  • Next
Auth0 Logo