How to design a planet
- Pick an orbit. A hot orbit, close to the star, dries the land and melts the ice. A cold orbit spreads ice caps toward the equator. Temperate sits in the middle of the habitable zone.
- Set the climate. Dry planets grow deserts; wet planets grow forests.
- Choose how much land you want. At 0% you get an ocean world; at 100%, a planet with no seas at all. Earth is about 29% land.
- Try new shapes. Press Random for a different arrangement of continents. Each shape has a number (its seed) — the same number always produces the same planet.
- Sculpt. Choose a brush, then click or drag on the planet. Raise mountains, flood valleys, plant forests or freeze a coastline.
- Share it. Save a picture of your planet, or copy a link that opens it exactly as you left it.
The science behind the settings
Every option in this tool matches a step in our guide to how planets are built:
- Orbit — distance from the star sets the temperature. See Step 2: Choosing the orbit.
- Mountains and terrain — shaped by a planet's interior and crust. See Step 3: Building the core and crust.
- Atmosphere glow — the thin blue halo is the air. See Step 4: Adding an atmosphere.
- Land and sea — see Step 5: Bringing water.
- Ice caps form near the poles because sunlight arrives at a low angle there, spreading the same energy over a larger area.
Why hexagons?
Your planet's surface is divided into 4,002 tiles. Covering a sphere with equal-sized tiles is a surprisingly hard geometry problem — squares distort badly near the poles. Hexagons fit together almost evenly, but mathematics says you can never cover a sphere with hexagons alone: you always need exactly 12 pentagons, just like the panels on a classic football. We hide those 12 pentagons in the ocean. Can you find them?
What does the habitability score mean?
The score is a playful summary, not a scientific measurement. It rewards a temperate orbit, plenty of open water with some land, and green regions, and it goes down for ice and deserts. Real habitability depends on many more factors — read Step 6: Making it habitable.
Is my planet saved?
Your planet lives in the page address. Copy the link to keep it or send it to friends — opening the link rebuilds the planet exactly. Nothing is uploaded to our servers.