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

  • Build Agents and Models on One Platform Icon
    Build Agents and Models on One Platform

    Everything you need to build production-ready agents and models. Access 200+ Google and third-party AI models and tools.

    Gemini Enterprise Agent Platform is Google Cloud's comprehensive platform for developers to build, scale, govern, and optimize agents and models. Choose from Google's most advanced models and third-party models like Anthropic's Claude Model Family.
    Start Free
  • Paessler: Easy to Use With Enterprise Power. Free Trial Icon
    Paessler: Easy to Use With Enterprise Power. Free Trial

    A low-code dashboard makes monitoring intuitive for any admin, while scripting and custom sensors give experts full control.

    You shouldn't have to choose between a monitoring tool that's easy to use and one that's powerful enough for a complex environment. PRTG's low-code interface lets any admin build dashboards, set alerts and monitor devices without scripting, while custom sensors and full API access are there when your team needs deeper control. One platform, no compromise. Download a free 30-day trial now.
    Get Free Download
  • 1

    TILP - TI Linking Program

    TI graphing calculators <-> computer communication software

    TILP (formerly GtkTiLink) can transfer data between Texas Instruments graphing calculators and a computer. It works with all link cables (parallel, serial, Black/Gray/Silver/Direct Link) and it supports the TI-Z80 series (73..86), the TI-eZ80 series (83PCE, 84+CE), the TI-68k series (89, 92, 92+, V200, 89T) and the Nspire series (Nspire Clickpad / Touchpad / CX, both CAS and non-CAS). The project is now managed on Github, https://github.com/debrouxl/tilp_and_gfm . It uses the libti* libraries, https://github.com/debrouxl/tilibs . Install script for *nix: https://github.com/debrouxl/tilp_and_gfm/blob/master/tilp/trunk/build/scripts/install_tilp.sh
    Leader badge
    5.0 out of 5 stars 5 Reviews
    Downloads: 487 This Week
    Last Update:
    See Project
  • 2
    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
    5.0 out of 5 stars 4 Reviews
    Downloads: 307 This Week
    Last Update:
    See Project
  • 3
    Open Tax Solver

    Open Tax Solver

    Calculates income tax form entries, helps do your taxes.

    OTS is a safe, secure, easy-to-use program for calculating Tax Return Form entries, and determining your tax-owed or refund-due, for Federal or State personal income taxes. Includes updated versions for US 1040, Schedules A, B, C, D, and for several states. OTS provides both graphical and textual interfaces for quickly filing out your tax forms. --- Best way to download the correct version for your platform -- go to the OTS WEBSITE: =====> https://opentaxsolver.sourceforge.net/
    Leader badge
    3.7 out of 5 stars 10 Reviews
    Downloads: 126 This Week
    Last Update:
    See Project
  • 4
    This emulator is capable of providing a faithful replication of the HP48. It also has a debugger for the saturn processor.
    Leader badge
    5.0 out of 5 stars 4 Reviews
    Downloads: 69 This Week
    Last Update:
    See Project
  • Endpoint Management with Remote Control Built In Icon
    Endpoint Management with Remote Control Built In

    Patch, monitor, and connect to Windows and macOS devices from one console

    Splashtop AEM handles patching, alerts, scripts, and inventory, and unattended remote control is included. When something needs hands-on work, you’re one click away instead of switching tools.
    Start Free Trial
  • 5
    Osmo
    Osmo is a handy personal organizer, which includes calendar, tasks manager, address book and notes modules. It was designed to be a small, easy to use and good looking PIM tool to help to manage personal information.
    Leader badge
    4.6 out of 5 stars 23 Reviews
    Downloads: 35 This Week
    Last Update:
    See Project
  • 6
    MultiPar

    MultiPar

    Parchive tool

    MultiPar is a Windows file recovery utility that creates and processes parity files to protect data against corruption or loss. It uses the Parchive system to generate recovery information for selected files and directories. Users can verify file integrity and repair damaged or missing data when sufficient recovery blocks are available. The application supports PAR2 recovery files alongside checksum verification using SFV and MD5 formats. Additional verification options help locate files that have been moved or renamed. FLAC fingerprint support enables integrity checking for compatible audio collections. Its recovery engine can use multicore processing and compatible GPU acceleration. MultiPar is particularly useful for protecting archives, backups, and large file collections.
    Downloads: 6 This Week
    Last Update:
    See Project
  • 7
    'atlc' is a CAD package used for analysing and desiging electrical transmission lines of arbitrary cross section. Also for the design of directonal couplers. Some parts are CPU intensive, so multiple CPUs are supported.
    Leader badge
    5.0 out of 5 stars 2 Reviews
    Downloads: 50 This Week
    Last Update:
    See Project
  • 8
    Advanced Trigonometry Calculator

    Advanced Trigonometry Calculator

    Open-source C/C++ math engine for advanced scientific computing

    Advanced Trigonometry Calculator (ATC) is an open-source mathematical computing engine written mainly in C/C++. Created in 2011 and maintained by Renato Alexandre dos Santos Freitas, ATC is designed as a practical Windows desktop application for advanced calculations, automation, and technical problem solving. ATC supports equation solving, polynomial tools, complex numbers, matrix calculations, statistics, physics, geometry, unit conversions, DSP/FFT operations, and scripting. It can also process batch TXT files, making it useful for repeatable calculations and automated workflows. The project also includes ATC Online Alpha, a WebAssembly-based version that brings parts of the ATC engine to the web. ATC is released under the GPLv3 license and is made in Portugal.
    Leader badge
    5.0 out of 5 stars 2 Reviews
    Downloads: 48 This Week
    Last Update:
    See Project
  • 9
    WP 34s

    WP 34s

    Scientific/engineering firmware repurposing HP business calculators!

    This project has created scientific firmware for the HP-20b and HP-30b business calculators. WP 34S turns either of these calculators into a powerful keystroke programmable scientific device. According to our customers, it's the most powerful and fastest RPN scientific pocket calculator ever built. WP 34S is alive and stable since 2011. We have succeeded in satisfying the most picky users - read about their experiences on http://www.hpmuseum.org/forum/forum-8.html. Since 2014, WP 34S runs in version 3.3. Our customers confirm its documentation is excellent and comprehensive (see feedback); a full-color printed edition is available from https://www.amazon.com/dp/153366238X since 2018-10-15. Alternatively, you can get a personalized pdf-manual for a ≥ 9 US$ donation here. We have also produced the WP 31S which is derived from the WP 34S source code. This is an entry-level scientific calculator. Its printed manual is available from https://www.amazon.com/dp/1499231164 .
    Leader badge
    5.0 out of 5 stars 7 Reviews
    Downloads: 25 This Week
    Last Update:
    See Project
  • Earn up to 16% annual interest with Nexo. Icon
    Earn up to 16% annual interest with Nexo.

    More flexibility. More control.

    Generate interest, access liquidity without selling, and execute trades seamlessly. All in one platform. Geographic restrictions, eligibility, and terms apply.
    Get started with Nexo.
  • 10
    4tH compiler

    4tH compiler

    A friendly Forth compiler with a little difference

    4tH is a Forth compiler with a little difference. Instead of the standard Forth engine it features a conventional compiler. 4tH is a very small compiler that can create bytecode, C-embeddable bytecode, standalone executables, but also works fine as a scripting language. It supports about 95% of the ANS Forth CORE wordset and features conditional compilation, pipes, files, assertions, forward declarations, enumerations, structures, suspended execution, recursion, include files, etc. It comes with an RPN calculator, BASIC interpreter, line editor, preprocessor, compiler, decompiler, C-source generator, a virtual machine, and a multitasking environment.
    Leader badge
    Downloads: 83 This Week
    Last Update:
    See Project
  • 11
    HashCheck

    HashCheck

    HashCheck Shell Extension for Windows with added SHA2, SHA3

    HashCheck is a free, open-source Windows shell extension that calculates and verifies file checksums directly from File Explorer. It adds a Checksums tab to file properties, making hash values accessible without separate command-line tools. Users can generate checksum files for individual files, multiple selections, or entire directories. The application verifies downloaded files against existing checksum records to detect corruption or unintended changes. Supported algorithms include CRC32, MD4, MD5, SHA-1, SHA-2, and SHA-3 variants. Multithreaded processing improves performance when calculating checksums for large collections. HashCheck supports SFV and other common checksum file formats. Its lightweight architecture provides multilingual interfaces and native Windows Explorer integration.
    Downloads: 3 This Week
    Last Update:
    See Project
  • 12
    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.
    5.0 out of 5 stars 2 Reviews
    Downloads: 17 This Week
    Last Update:
    See Project
  • 13

    galculator

    galculator is a scientific calculator in algebraic mode and RPN

    galculator is a GTK 2 / GTK 3 based scientific calculator supporting algebraic mode as well as RPN. Features include arithmetic precedence handling, mathematical functions, different number bases (DEC, HEX, BIN, OCT) and angle bases (radiant, degree, and grad). Please note: This project page at sf.net reflects the state of the project up to August 2015. Beginning in September 2015, the project homepage was moved to http://galculator.mnim.org, with the source code repositories and issue trackers hosted at https://github.com/galculator/galculator.
    Leader badge
    4.3 out of 5 stars 3 Reviews
    Downloads: 13 This Week
    Last Update:
    See Project
  • 14
    Scientific calculator for PalmOS and PocketPC with graphing, financial operations, number conversions, complex numbers and much more.
    5.0 out of 5 stars 3 Reviews
    Downloads: 8 This Week
    Last Update:
    See Project
  • 15
    fHash

    fHash

    A files hash calculator for Windows and macOS.

    An open source files hash calculator for Windows and macOS. * MD5, SHA1, SHA256 and SHA512. * Drag & drop. * Integrated with context menu in Explorer/Finder. * Support Windows 7 and later. * Support macOS 13 and later, with universal binary. * Support Dark Mode. * English and Simplified Chinese UI. The icon "希" is from hash in Chinese "哈希".
    Leader badge
    5.0 out of 5 stars 1 Review
    Downloads: 12 This Week
    Last Update:
    See Project
  • 16
    HexTool is a simple yet effective calculator/tool; invaluable for people who work with Hex and Binary. Now you can convert between Hex, Binary and Decimal on the fly. No install needed: just unzip and run it!
    4.0 out of 5 stars 1 Review
    Downloads: 10 This Week
    Last Update:
    See Project
  • 17
    ReHash is an easy-to-use console-based hash calculation tool written in C++. It supports many algorithms and output formats and it can be fully configured using some of the many command-line arguments which can be passed to the tool.
    5.0 out of 5 stars 2 Reviews
    Downloads: 6 This Week
    Last Update:
    See Project
  • 18

    calc: C-style arbitrary precision system

    Calc: arbitrary precision C-like arithmetic & calculator

    Calc is arbitrary precision C-like arithmetic system that is a calculator, an algorithm prototyper and mathematical research tool. Calc comes with a rich set of builtin mathematical and programmatic functions.
    Leader badge
    5.0 out of 5 stars 5 Reviews
    Downloads: 3 This Week
    Last Update:
    See Project
  • 19
    Wcalc

    Wcalc

    A powerful arbitrary-precision calculator.

    Wcalc is a powerful arbitrary-precision calculator. It has standard functions (sin, asinh, logtwo, floor, etc), many pre-defined constants (pi, e, c, etc.), variables, "active" variables, command history, and hex/octal/binary i/o, conversions, and more
    Leader badge
    Downloads: 12 This Week
    Last Update:
    See Project
  • 20
    A simple command to convert calendar dates to julian dates. Quite useful in timing situations where you need elapsed time between dates. Also useful for astronomy applications.
    Leader badge
    Downloads: 8 This Week
    Last Update:
    See Project
  • 21
    NOTE: Moved to https://github.com/vapier/pcalc Pcalc is a command line calculator handling HEX DEC OCT BIN. It can process a script, save variables to file, full math parser, parentheses, exponential, sin/cos, sqrt, date, inch/mm celsius/f, compound expressions ...
    Leader badge
    Downloads: 8 This Week
    Last Update:
    See Project
  • 22
    Getting your first mortgage? No, this isn't spam, its mort! A simple but powerful loan/mortgage calculator that also amortizes.
    Leader badge
    Downloads: 7 This Week
    Last Update:
    See Project
  • 23
    LibG100 is a common library to use all capacity of the Casio Afx2/Graph100 Calculator
    Downloads: 6 This Week
    Last Update:
    See Project
  • 24
    Interest(ing) Calculator is useful in calculating Financial Parameters of loans/deposits.Loan/Deposits have four variables.They are, Principal,Interest Rate,Term,Installment.IC helps to calculate any one variable, if you know the other three variables.
    Downloads: 5 This Week
    Last Update:
    See Project
  • 25
    ReactOS Calc is a scientific calculator. It has been written to be a clone of calculators included into MS Win32 operating systems. It has a similar user interface and keyboard shortcuts. It will be released under GNU GPL license.
    Downloads: 5 This Week
    Last Update:
    See Project