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.

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  • 1
    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/
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    Downloads: 373 This Week
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  • 2

    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
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    Downloads: 361 This Week
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  • 3
    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.
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    Downloads: 113 This Week
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  • 4
    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.
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    Downloads: 32 This Week
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  • 5
    This emulator is capable of providing a faithful replication of the HP48. It also has a debugger for the saturn processor.
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    Downloads: 35 This Week
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  • 6
    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 .
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    Downloads: 28 This Week
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  • 7
    4tH compiler

    4tH compiler

    A 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.
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    Downloads: 94 This Week
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  • 8
    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".
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    Downloads: 27 This Week
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  • 9
    Advanced Trigonometry Calculator

    Advanced Trigonometry Calculator

    Precision Trigonometry: Advanced Calculator for Complex Math

    Advanced Trigonometry Calculator is equipped with a user-friendly interface that allows for easy input of problems and instant computation. Professionals such as engineers who need to perform advanced trigonometric calculations in their work will find this tool extremely useful. ATC Online Alpha: https://advantrigoncalc.sourceforge.io/atc/ More info by clicking below: https://advantrigoncalc.sourceforge.io/ Advanced Trigonometry Calculator was only and always only developed by the Portuguese Renato Alexandre dos Santos Freitas. Also author of poems, reflections and thoughts published on the platform https://www.pensador.com/autor/renato_alexandre_dos_santos_freitas/ ATC is Made in Portugal. He was born in Coimbra on July 6, 1991. He has a degree in Electrical and Telecommunications Engineering and began developing ATC at the beginning of his undergraduate studies. He works for Miclearning, Lda since April 2020. Providing services to Multimac Hito Innovation.
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    Downloads: 15 This Week
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  • 10
    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.
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    Downloads: 12 This Week
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  • 11

    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.
    Downloads: 6 This Week
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  • 12
    OpenDRO
    OpenDRO is an open source project to develop embedded software that runs on digital readouts (DROs) for lathes, mills, and other machine tools.
    Downloads: 12 This Week
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  • 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.
    Downloads: 6 This Week
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  • 14
    OptionMatrix

    OptionMatrix

    Financial Derivatives Calculator with 171+ Models (Options Calculator)

    A real-time financial derivatives calculator supporting 171+ models from QuantLib, Financial Numerical Recipes in C++ and MetaOptions. Matrices of prices are created with iterating strikes and/or months. A strike control system can produce any strike. A generalized date engine can calculate re-occuring distances to any industry used expiration into the future. Spread engine with spread views. Models Supported: Black-Scholes, Merton-73, Black-76, Roll Geske Whaley, Garman KohlHagen, Jump Diffusion, Quanto, Vasicek Bond Option, Turnbull Wakeman Asian, TimeSwitchOption, Look Barrier, Bachelier, PartialTimeBarrier, GapOption, Extreme Spread Option, Simple Chooser, ComplexChooser, PartialFixedLB, Executive, CashOrNothing, Extendible Writer, OptionsOnOptions, BAWAmericanApprox, BSAmericanApprox, AssetOrNothing, Bisection, BAWbisection, BSbisection, Gfrench, Gcarry, Swapoption, Complex Chooser, Super Share, EquityLinkedFXO, Spread Approximation, BinaryBarrier and more
    Downloads: 5 This Week
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  • 15
    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.
    Downloads: 7 This Week
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  • 16
    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
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    Downloads: 15 This Week
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  • 17
    Getting your first mortgage? No, this isn't spam, its mort! A simple but powerful loan/mortgage calculator that also amortizes.
    Downloads: 10 This Week
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  • 18
    Scientific calculator for PalmOS and PocketPC with graphing, financial operations, number conversions, complex numbers and much more.
    Downloads: 2 This Week
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  • 19
    QxCalc

    QxCalc

    QxCalc, a scriptable calculator

    QxCalc For mathematical calculations in high-school, physics, chemistry, mathematics, economics, electrical, mechanical. Create equations, and also calculate with them, with ease. You use the calculator the same way as you use a pen and paper. It is quite simple, and can do a lot of work given syntax correctness. It comes with a "basic" gui, however the best way to use it is with the 'vim' editor, for which it has a syntax highlight file (calc.vim).
    Downloads: 6 This Week
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  • 20
    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 ...
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    Downloads: 5 This Week
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  • 21
    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!
    Downloads: 2 This Week
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  • 22
    Big Numbers Calculator
    Arithmetic, bitwise and base conversion operations over the big integers.
    Downloads: 3 This Week
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  • 23
    Evalute mathematic expression in console. Released many functions and operations.
    Downloads: 3 This Week
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  • 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: 3 This Week
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  • 25

    Timer Calculator for any MCU

    Tired of boring calcs? Let me simplify your Timer based projects.

    A simple program that calculates up to 6 parameters to help you using Timers. It is done to be used with ever single MCU (PIC, ATMEL, Freescale, etc) and plataform (Arduino, Raspberry, Edison, etc). Just enter yours parameters and let the program calculate all the needed values to help you. It also saves a .txt file with results, if you need to see it again later and save your inserted values (no one likes to retipe values everytime, right?) Isn't program translated to your language? Use the e-mail in the program to know how to translate the program to your language. Missing feature? Contact via email too. Want to help me to develop for Mac or Linux? You know the way (:
    Downloads: 3 This Week
    Last Update:
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