A 2D spaceflight sandbox
Build rockets, planes and stations with a custom spaceflight physics engine. Fly the solar system and other galaxies, on your own or in multiplayer.
Free beta. In active development.
The solar system, then other stars
Start around Earth. Land on the Moon, plan a transfer to Mars, or build a craft for a longer trip. Sandbox includes real nearby stars and generated systems across the galaxy.
Explore the universe →
Real scale, with smaller options. Fly the full-size solar system, or choose 1:10 or 1:20 for shorter trips.
Interstellar flight. Travel with engines and time warp. Sandbox only, with the default gravity model.
Build a station with friends
Fly your own craft in a shared Sandbox world. Dock, transfer fuel, ride along or spectate a launch. Each player can time warp and use SYNC to meet up again.
Multiplayer and server hosting →Host from the game with a room code, or run a dedicated Linux server. Everyone joining needs the same game version. Journeys between stars are private until you arrive and SYNC.
A builder for more than rockets
Place and resize parts, arrange stages, and paint your craft. Hinges, pistons, ropes and wheels also make rovers, planes and moving machines.
Building tools and flight physics →

- Career
- Missions introduce flight, landings and longer trips. Earn parts as you progress.
- Flight physics
- Orbital mechanics, atmospheric drag, re-entry heating and buoyancy affect your craft.
- EVA and construction
- Leave a capsule, use a jetpack, plant flags and work with parts outside your craft.
- Mission Lab
- Build flight programs for tasks such as ascent, landing and rendezvous.
- Surface colonies
- Survey deposits, land equipment and launch new craft from colony pads.
- Paint and decals
- Paint on parts and add your own text and images.

Make your own parts and worlds
Body Studio edits planets, moons and stars. The part editor and Engine Lab let you change hardware, mechanisms and engine plumes without writing code.
Share a mod or a complete world as a file. The Community Hangar has player-made rockets and mods to download.
Browse the Community Hangar →View all gameplay images →Before you download
Is Rocket Foundry free?
The beta is free on Windows, macOS, Linux, Android and iOS. The game is in active development, so features and performance change between releases.
Is it an alternative to Spaceflight Simulator (SFS)?
Yes. Rocket Foundry combines 2D rocket building with a custom spaceflight physics engine, multiplayer, planes and solid rocket boosters. You can program flights, build colonies, and explore star systems in the Milky Way and other galaxies. It is an independent game, currently in free beta.
Can I play with friends?
Yes. Host a Sandbox world and share a room code, join by server address, or run a dedicated Linux server. Players can dock, chat, spectate and use independent time warp, then SYNC to meet again.
Do I have to play at real scale?
The solar system is full size by default. You can choose a smaller 1:10 or 1:20 world instead, with the same rockets and surface gravity.
Can I explore other stars?
Yes, in Sandbox with the default gravity model. Travel uses your craft's engines and time warp. Career stays in the solar system.
Can I make and share mods?
Yes. The game includes editors for parts, moving mechanisms, engine plumes, planets and star systems. Share mods and worlds as files, or browse rockets and mods in the Community Hangar.
Try the beta
Free on Windows, macOS, Linux, Android and iOS.