CalcpadCE

Open-source mathematical and engineering calculations – Community Edition

Input

Result

Enter code and press Convert

Settings

Math

Decimal Places

Angle Units

Complex Numbers Substitution Format Equations

Plot

Color Scale

Light Direction

Shadows Vector Graphics

Display

Theme

What is CalcpadCE?

CalcpadCE is an open-source tool for mathematical and engineering calculations. Write your formulas in a simple, readable syntax and get beautifully rendered output with plots, diagrams, and formatted results — all in real time. For Desktop, Web and Visual Studio Code.

This is a fork of the now closed-source Calcpad (March 2026).

View Documentation Quick Reference

Examples

Real worksheets across maths, physics and engineering. Click a thumbnail to enlarge, follow the link to open the live example.

Getting Started

Write math the way you'd jot it on paper. No syntax to memorise, no formula editor to fight: variables, units and built-in constants just work, and every result updates the moment you change an input.

View unit conversion examples and more

Enlarge: CalcpadCE source on the left with commented expressions (arithmetic, comparisons, variables, constants, an integral, matrix multiplication) rendered as a formatted worksheet on the right — Easy to use for simple math —

Close — Easy to use for simple math —

Finite Element Analysis

Plane-stress FEA of a deep beam using rectangular 8-DOF elements, with a partial uniform load and elastic supports modelled by a distributed-stiffness function. Recovers the 𝜎_𝑥, 𝜎_𝑦 and 𝜏_𝑥⁢𝑦 stress fields and the deflected shape on a parametric mesh.

View more examples like this

Enlarge: CalcpadCE source defining membrane-force equations on the left, a coloured N_xy stress contour map and the deflected-shape curve of the deep beam on the right — — Built for real-world engineering.

Close — — Built for real-world engineering.

3D, Plotting, Animating 🎬

Animate a parametric plot frame by frame: a for loop emits one hidden div per frame, and a tiny setInterval script cycles through them in the browser. The same pattern works for any time- or parameter-dependent function.

View this animation and explore other 3D examples

Enlarge: CalcpadCE source with a #for loop emitting plot frames and a setInterval script on the left, and the rendered heart-shaped sinusoidal curve on the right — Plotting arbitrary curves

Close — Plotting arbitrary curves

Elasticity Analysis 🎬

Two-DOF elastic pendulum: the rigid rod is replaced by an axial spring of stiffness 𝑘_𝑠, giving coupled radial and angular equations of motion with independent damping factors. RK4 integration drives the SVG animation.

View this animation and explore more

Enlarge: Time-series plots of the pendulum angle and spring length on the left, and an SVG rendering of the pendulum tracing its looping trajectory on the right — Elastic Pendulum

Close — Elastic Pendulum

Wave Simulation

The spatial view of the famous Double-Slit Experiment: two coherent point light sources separated by 𝑑 =3 𝜇⁢𝑚 are summed on a 2D grid to plot the full Ψ⁡(𝑥, 𝑦) field.

View more examples like this

Enlarge: CalcpadCE source defining the two-source wave field on the left, fully formatted derivations of the wave constants, and a 2D intensity heatmap showing the radial interference fringes on the right — Interference of Light

Close — Interference of Light

Browse All Examples

Over 200 ready-to-run examples cover structural and geotechnical engineering, mechanics, physics, maths and more. Open one, tweak the inputs, and make it yours.

All examples

200+

Get CalcpadCE for Desktop

CalcpadCE 7.6.4

Download the native Desktop application. Please note that Linux packages are command-line only.

Download for Windows Download for Linux

Windows Installer (64-bit)

Windows Portable (64-bit)

Debian/Ubuntu (64-bit .deb)

Debian/Ubuntu (ARM .deb)

CentOS/Fedora (64-bit .rpm)

CentOS/Fedora (ARM .rpm)

Portable Linux (64-bit .tar.bz2)

Portable Linux (ARM .tar.bz2)

CalcpadCE for Visual Studio Code

The community-driven Visual Studio Code extension bringing CalcpadCE to your favorite editor. Cross-platform, actively developed, and open source.

Get VSC Extension

Join the Community

CalcpadCE is built by engineers, for engineers. Get involved, ask questions, or help shape the future of the project.

Contribute on GitHub

Browse the source code, report issues, submit pull requests, or star the project to show your support.

View repository

Join the Discord

Ask questions, share your work, get help from other engineers, and chat with the development team in real time.

Forum & Discussions

Start or join longer-form conversations about features, ideas, best practices, and the future direction of CalcpadCE.

Browse discussions

What Happened to the Original Calcpad?

Following a shift to a closed-source model by its original creator, the public GitHub repository for Calcpad was taken offline.

Our community stepped up to fork the project and continue its open-source development. We restored the final open-source release to officially launch CalcpadCE as a free, community-driven continuation of the software.

Our collective goal is to maintain and grow this incredible tool, ensuring it remains freely available for the professionals who rely on it.

As we evolve the software, we are improving the core language by adding features like strings and keyword arguments to simplify complex coding. We are also focused on modernizing the overall development experience with enhanced tooling, including dedicated editor extensions.

Whether you want to contribute code, report issues, or simply spread the word — we invite you to join us and help CalcpadCE thrive!