Three-Body Simulator: Interactive 3D browser simulator for three-body problem orbits.

What it does

Three-Body Simulator is a browser-based tool for visualizing gravitational orbits in real time. Users can load preset periodic orbits or create custom configurations by setting masses and velocities for multiple bodies. The simulator computes gravitational interactions and renders the resulting motion in interactive 3D space. Core features include several dozen preset orbits (both classic and newly discovered solutions), full 3D camera controls with body-following mode, vector visualization for forces and velocities, and timeline scrubbing to explore complete orbital periods.

Who it is for

The tool appeals to physics students, researchers, and anyone curious about celestial mechanics and the three-body problem. Educators may use it to demonstrate gravitational dynamics without coding. The interface supports both simple exploration (loading presets) and advanced configuration (setting custom masses, positions, and velocities, adjusting numerical methods and tolerances).

Pricing

The site does not show prices. The simulator is free to use in the browser.

How it stands out

The primary distinction is the preset library sourced from Li and Liao's 2025 database of over 10,000 newly discovered three-dimensional periodic orbits. Most gravity simulators focus on two-body systems or general N-body dynamics; this one emphasizes exact three-body choreographies. The simulator offers multiple numerical integration methods (Velocity Verlet, RK4, Kepler exact solver, and adaptive Cash-Karp) and fine-grained controls for softening, timestep, and tolerance—options typically found in research software rather than educational demos. Anaglyph 3D support and keyboard shortcuts optimize for keyboard-driven exploration.

What a founder should check

A competitor should verify the accessibility and citation of the Li and Liao orbit database, since it is the primary draw. Check whether users can easily export or share configurations; the interface hints at screenshot and share functionality, but depth of integration matters. Finally, assess numerical stability claims: the site warns that orbits drift after many cycles due to integration limits, and rotating polygon configurations are marked quasi-stable. A rival must clarify what accuracy benchmarks they meet and whether they justify higher-order integrators or different algorithms to reduce drift.

Thinking of building something like this?

Every launch here is a competitor to somebody's idea. If yours is close, check it against the market before you build: the Full Check names the rivals, the prices and the gaps.