Interactive Physical Simulator

Updated 10 days agoActively maintained
Arch Linux (recommended) Debian Ubuntu Fedora openSUSE Alpine Linux Slackware Nixpkgs

Screenshots & videos

About

Step is an interactive physical simulator. It allows you to explore the physical world through simulations. It works like this: you place some bodies on the scene, add some forces such as gravity or springs, then click Simulate and Step shows you how your scene will evolve according to the laws of physics. You can change every property of the bodies/forces in your experiment (even during simulation) and see how this will change evolution of the experiment. With Step you cannot only learn but feel how physics works! Features: - Classical mechanical simulation in two dimensions - Particles, springs with damping, gravitational and coulomb forces - Rigid bodies - Collision detection (currently only discrete) and handling - Soft (deformable) bodies simulated as user-editable particles-springs system, sound waves - Molecular dynamics (currently using Lennard-Jones potential): gas and liquid, condensation and evaporation, calculation of macroscopic quantities and their variances - Units conversion and expression calculation: you can enter something like "(2 days + 3 hours) * 80 km/h" and it will be accepted as distance value (requires libqalculate) - Errors calculation and propagation: you can enter values like "1.3 ± 0.2" for any property and errors for all dependent properties will be calculated using statistical formulas - Solver error estimation: errors introduced by the solver is calculated and added to user-entered errors - Several different solvers: up to 8th order, explicit and implicit, with or without adaptive timestep (most of the solvers require GSL library) - Controller tool to easily control properties during simulation (even with custom keyboard shortcuts) - Tools to visualize results: graph, meter, tracer - Context information for all objects, integrated wikipedia browser - Collection of example experiments, more can be downloaded with KNewStuff - Integrated tutorials

Additional information

Project

License
GPL-2.0+ (free software)What this license lets you do
Latest release
October 8, 2026 (10 days ago)Actively maintained · 10+ releases in the last year
Release history
Last 10 releases
  • 26.08.2October 8, 2026
  • 26.08.1September 10, 2026
  • 26.08.0August 20, 2026
  • 26.04.3July 2, 2026
  • 26.04.2June 4, 2026
  • 26.04.1May 7, 2026
  • 26.04.0April 16, 2026
  • 25.12.3March 5, 2026
  • 25.12.2February 5, 2026
  • 25.12.1January 8, 2026
Languages
50 languages

Install

Available via
Arch Linux (2) · Debian · Ubuntu · Fedora · openSUSE · Alpine Linux · Slackware · Gentoo · Nixpkgs
All 10 packagings

AUR (Git build), Debian, Ubuntu, Fedora, Arch Linux, Nixpkgs, openSUSE, Alpine Linux, Slackware, Gentoo (Candidate build)

About this data

Sources
15 independent sources agree
Catalog data as of
October 12, 2026
How each source lists it (10)
SourceNameVersionBuilt byLicenseDescription
AUR (Git build)step-git24.04.70_r1422.gbe025ee-2—GPL-2.0-or-later AND LGPL-2.0-or-laterInteractive Physical Simulator
Debianstep4:25.04.0-1Distribution build—interactive physical simulator for KDE
Ubuntustep4:25.12.3-0ubuntu1Distribution build—interactive physical simulator for KDE
Fedorastep26.08.1Distribution buildGPL-2.0-or-laterInteractive Physics Simulator
Arch Linuxstep26.08.2-1Distribution buildGPL-2.0-or-later AND LGPL-2.0-or-laterInteractive Physical Simulator
Nixpkgsstep26.08.2Distribution buildBSD-2-Clause AND BSD-3-Clause AND CC0-1.0 AND GPL-2.0-or-later AND LGPL-2.1-only AND LGPL-3.0-only AND LGPL-3.0-or-laterInteractive physics simulator
openSUSEstep26.08.2Distribution buildGPL-2.0-or-laterAn interactive physics simulator
Alpine Linuxstep26.04.2-r0Distribution buildGPL-2.0-or-later AND GFDL-1.2-onlyInteractive Physics Simulator
Slackwarestep26.08.2-1Distribution build—step (interactive physics simulator)
Gentoo (Candidate build)step26.08.2Distribution buildGPL-2.0-onlyInteractive physics simulator

Related

Weasis

Science

Free medical DICOM viewer

4 platformsFlatpak (recommended, ✓ verified) Snap Arch Linux Nixpkgs5 buildsStandard: Stable Standard: Candidate Standard: Beta Standard: Nightly Other builds: BinFlathub (Flatpak): ★ 4.4 (19)

ImageJ

Science

Image processing and analysis

6 platformsArch Linux (recommended) Debian Ubuntu Fedora openSUSE Nixpkgs

sigrok

Science

sigrok suite (sigrok-cli and pulseview)

Snap (recommended) Debian Ubuntu3 buildsStandard: Beta Standard: Nightly Standard: Stable

CoMaps

Science

Free offline maps for everyone

Flatpak (recommended, ✓ verified) Arch Linux NixpkgsFlathub (Flatpak): ★ 3.4 (7)

Fityk

Science

Curve fitting tool

8 platformsFlatpak (recommended) Arch Linux Debian Ubuntu Fedora openSUSE Gentoo Nixpkgs3 buildsStandard: Stable Standard: Git Standard: Candidate

KAlgebra

Science

Graph Calculator

11 platformsFlatpak (recommended, ✓ verified) Snap Arch Linux Debian Ubuntu Fedora openSUSE Alpine Linux Slackware Gentoo Nixpkgs4 buildsStandard: Stable Standard: Beta Standard: Git Standard: CandidateFlathub (Flatpak): ★ 2.4 (18)

Cantor

Science

Frontend to mathematical software

11 platformsFlatpak (recommended) Snap Arch Linux Debian Ubuntu Fedora openSUSE Alpine Linux Slackware Gentoo Nixpkgs4 buildsStandard: Stable Standard: Beta Standard: Git Standard: CandidateFlathub (Flatpak): ★ 3.0 (9)

wxMaxima

Science

A graphical user interface for Maxima, a powerful computer algebra system

12 platformsFlatpak (recommended) Snap AppImage Arch Linux Debian Ubuntu Fedora openSUSE Void Linux Solus Gentoo Nixpkgs4 buildsStandard: Stable Standard: Nightly Standard: Git Standard: CandidateFlathub (Flatpak): ★ 4.5 (10)

KmPlot

Science

Mathematical Function Plotter

12 platformsFlatpak (recommended) Snap Arch Linux Debian Ubuntu Fedora openSUSE Alpine Linux Void Linux Slackware Gentoo Nixpkgs4 buildsStandard: Stable Standard: Beta Standard: Candidate Other builds: 32bitFlathub (Flatpak): ★ 3.3 (3)

Kalzium

Science

Periodic Table of Elements

12 platformsFlatpak (recommended) Snap Arch Linux Debian Ubuntu Fedora openSUSE Alpine Linux Slackware Solus Gentoo Nixpkgs4 buildsStandard: Stable Standard: Beta Standard: Git Standard: CandidateFlathub (Flatpak): ★ 4.5 (20)

KMeteo

Science

Weather forecasts, maps and data

Flatpak (recommended, ✓ verified) Snap Arch Linux3 buildsStandard: Stable Standard: Beta Standard: NightlyFlathub (Flatpak): ★ 4.0 (1)

Add-ons

Plugins (1)
  • step-kms-plugin — Step plugin to manage keys and certificates on cloud KMSs and HSMs (Nixpkgs, Alpine Linux)