Falstad.com

What Falstad.com does

Falstad.com is a personal website and software portfolio operated by individual developer Paul Falstad as a sole proprietorship, dating back to source code copyrights of 1998. The site hosts a collection of interactive physics simulation applets — implemented originally in Java and progressively converted to JavaScript via Bob Hanson's SwingJS — covering wave phenomena (Ripple Tank, Loaded String, Rectangular Membrane, Bar Waves, 2D and 3D Wave), electrostatics, Fourier analysis, digital filters, circuit simulation, and a 3D perspective maze game. The core technology is a custom physics simulation engine that numerically solves wave equations with accurate boundary conditions, dispersion, and resonance behavior, exposed through both browser-based applets and standalone offline versions.

The product surface extends to native mobile and desktop applications, including Ripple Tank for iPhone/iPad/Mac/Windows, Fourier, Electrostatics, DigitalFilters, and the consumer-oriented Mega Photo app (100+ real-time camera effects) for iOS and Android. Revenue is generated through one-time paid app purchases on the Apple App Store, Google Play (Mega Photo freemium), and the Kagi Store ($9.99 per desktop license), while web applets remain free. Distribution is entirely digital and self-serve — no sales team, enterprise contracts, or resellers exist. The target customer base consists of physics and engineering students, educators, and hobbyists seeking interactive visualization tools, with discovery driven primarily by organic search and word-of-mouth in physics education communities.

The business operates without external funding, formal corporate structure, or disclosed employees beyond Paul Falstad himself. The GitHub presence (pfalstad/ripplegl) and open-source RippleGL project provide community visibility but no monetization mechanism. Documented product development activity clusters in 2014-2015, with limited evidence of subsequent expansion, suggesting the operation functions as a sustained independent venture rather than a growth-stage business.

Name

Falstad.com

Legal name

Paul Falstad

Website

https://falstad.com

Company type

Private

Founded year

1998

Operating status

Operating

Headcount range

1–10 employees

Short description

Falstad.com is the personal portfolio of sole-proprietor developer Paul Falstad, offering free interactive physics simulation applets (wave, membrane, electrostatics, circuit) and paid mobile/desktop apps (Ripple Tank, Mega Photo) serving physics students and educators globally.

Ownership category

akta.pro rank

GTM type

B2C

Offering type

Software

Cost components

Personnel, Technology or R&D, Operations

Revenue model

1. Mobile App Sales (iOS/macOS): Native apps sold through the Apple App Store including Ripple Tank (iPhone/iPad/Mac), Ripple Tank Free, Fourier, Electrostatics, and Digital Filters. Revenue generated from direct app purchases.
2. Desktop App Sales (Windows/Mac): Desktop versions of Ripple Tank sold through Kagi software store for Windows and Mac. Mega Photo for Android sold through Google Play Store. Revenue from one-time purchase prices.
3. Android App Sales: Mega Photo app distributed through Google Play Store as a free app with premium features, generating revenue from app downloads and in-app engagement.

Pricing tiers

Go-to-market motion1 record

Distribution channels4 records

Marketing channels6 records

Core offering

Falstad.com provides interactive physics simulation applets—primarily focused on wave mechanics (ripple tanks, vibrating strings, membranes, bar waves, 2-D and 3-D scalar waves)—delivered as free in-browser Java, JavaScript, and WebGL applications. These web applets are complemented by paid native mobile (iOS/Android) and desktop (Windows/Mac) apps, including a flagship Ripple Tank application, plus Fourier analysis, Electrostatics, Digital Filters, and a photo-effects app called Mega Photo.

Product overview

Falstad.com is a personal website by Paul Falstad offering a portfolio of interactive physics simulation applets and mobile/desktop applications. The core products are Java/WebGL applets demonstrating wave physics (Ripple Tank, Loaded String, Bar Waves, Membrane, 2D/3D Wave simulations) and educational games (Maze). Mobile and desktop versions of Ripple Tank are distributed via iOS App Store, Google Play, and direct sales. Additional apps include Fourier analysis, Electrostatics, Digital Filters, and Mega Photo (100+ photo effects). The products are primarily distributed as standalone Java applets, WebGL simulations, and native mobile/desktop applications, with some source code available on GitHub.

Differentiator

Problem solved

Functional benefit

Brands

• Mega Photo: Photo editing app with 100+ free real-time camera effects including tunnel, mosaic, puzzle, hue shift, motion blur, tile, emboss, spinning cube, x-ray, collage, night vision, halftone, light tunnel, and more. Available on iOS and Android.

Products and services

• Ripple Tank Simulation (Web Applet) Interactive simulation of a ripple tank demonstrating waves in two dimensions, including interference, diffraction (single slit, double slit), refraction, resonance, phased arrays, and the Doppler effect. Available as WebGL, JavaScript, and Java versions.
• Rectangular Membrane Applet Java/JavaScript applet simulating waves in a rectangular membrane (drum head) showing various vibrational modes with normal mode contributions, magnitude and phase indicators, and a 3-D view option.
• Loaded String Simulation Simulation demonstrating standing waves on a vibrating loaded string with multiple normal modes, harmonics, damping, driving force, and real-time audio synthesis.
• Bar Waves Applet Simulation of standing flexural waves in a bar with various boundary conditions (free, hinged, clamped), including stiff strings with adjustable stiffness.
• 3-D Perspective Maze Game Java-based maze game with 3D perspective view, automatic maze solving, multiple skill levels (0-F), and BSP-based room generation.
• 3-D Wave Simulation (WaveBox) Simulation demonstrating scalar waves (such as sound waves) in three dimensions, showing point sources, line sources, plane waves, and interference patterns.
• 2-D Wave Simulation Simulation demonstrating scalar waves in two dimensions, covering principles behind slit diffraction, zone plates, and holograms.
• Ripple Tank (iPhone/iPad App) Paid iOS version of the Ripple Tank simulation allowing wave creation with finger input, experiment saving, and full iPad optimization.
• Ripple Tank Free (iPhone/iPad App) Free iOS version of the Ripple Tank simulation with limited features compared to the paid version.
• Ripple Tank (Mac Desktop App) Mac desktop version of the Ripple Tank simulation distributed through iTunes/Mac App Store.
• Ripple Tank (Windows Desktop App) Windows desktop version of the Ripple Tank simulation sold for $9.99 through the Kagi Store, with ability to create/delete objects, save experiments, and record videos.
• Mega Photo Photo and video effects app with 100+ real-time camera effects including tunnel, mosaic, puzzle, hue shift, motion blur, emboss, spinning cube, x-ray, collage, night vision, halftone, and light tunnel. Available on iOS and Android.
• Math and Physics Applets Collection Collection page providing access to wave simulations, membrane simulations, and other educational physics demonstrations hosted at falstad.com.
• Circuit Simulator Interactive circuit simulation application available on the falstad.com platform.
• Fourier (Mac/Windows App) Fourier analysis application for Mac and Windows platforms, distributed through iTunes and the Kagi Store.
• Electrostatics (Mac/Windows App) Electrostatics simulation application for Mac and Windows platforms, distributed through iTunes and the Kagi Store.
• Digital Filters (Mac/Windows App) Digital filters application for Mac and Windows platforms, distributed through iTunes and the Kagi Store.

Segments1 record

Ideal customer profiles1 record

Technology focussed Yes

API detail

Has API

No

API docs

API detail

Core technology

AI maturity

App detail

Feature7 records

Scale indicators1 record

Recent moves6 records

Expansion highlights3 records

Direct peers

• PhET Interactive Simulations: University of Colorado Boulder's flagship interactive physics and math simulation platform. Offers free, browser-based simulations covering waves, circuits, and other physics topics, directly competing with Falstad's core educational physics simulation offerings.
• GeoGebra: Widely-used interactive mathematics and physics learning platform with graphing, geometry, and physics simulation tools. Targets overlapping student and educator audiences and is often deployed alongside physics curriculum resources.
• Open Source Physics: NSF-funded project providing open-source physics curriculum materials, simulations, and modeling tools. Shares Falstad's commitment to accessible physics education and addresses the same wave and mechanics topics.
• Algodoo: 2D physics simulation sandbox for education, allowing users to build and experiment with mechanical and optical systems. Targets the same physics education segment with interactive, visual simulation tools.
• EveryCircuit: Interactive circuit simulation app available on web, iOS, and Android. Explicitly referenced as a companion/related app on Falstad's own apps page, sharing the same developer audience and educational simulation category.
• Wolfram Demonstrations Project: Wolfram's open-code interactive demonstration library covering physics, math, and engineering topics. Provides browser-based, interactive visualizations similar to Falstad's wave and Fourier simulations.

Emerging players

• Desmos: Browser-based graphing calculator and math visualization platform with growing physics-adjacent capabilities. Targets the same student/educator demographic with free, interactive tools, though focused more on math than physics.
• The Physics Classroom: Long-standing educational website offering physics tutorials, interactive simulations, and concept-building resources. Targets the same high school and introductory physics student audience with complementary learning tools.

Broad incumbents

• Labster: Well-funded virtual science lab platform used by universities and schools, including physics simulations. Operates at a broader STEM-education scale with institutional sales, contrasting with Falstad's individual-developer model.
• Khan Academy: Large-scale educational platform with extensive physics content including videos, exercises, and some interactive simulations. Reaches the same student audience but as part of a much broader K-12 and early college curriculum offering.

Market position

Strengths4 records

Weaknesses5 records

Competitive moat4 records

Key risks6 records

Key highlights6 records

Customer concentration

• GitHubgithub.com/pfalstad/ripplegl

Revenue estimate

Valuation estimate

Number of profiles

Profiles1 record

Funding overview

Funding rounds

Investors

Funding detail is available on the Subscription and Enterprise plan.Contact sales →

M&A

Investments

M&A and investment is available on the Subscription and Enterprise plan.Contact sales →

Frequently asked questions about Falstad.com