Planet Generator

Use this planet generator to build planets for stories and games and class work.

Pick a type or let it surprise you.

The latest update adds a type selector and more traits like gravity and atmosphere.

You get a clean image of the planet and rings when present.

Each result feels unique.

The visual preview helps ideas land fast.

What the Planet Generator Does

The planet generator builds a full profile and a simple visual preview.

It creates values by type and by random rules.

• Planet name
• Type
• Diameter in kilometers
• Gravity in g, relative to Earth
• Atmosphere category
• Moons
• Surface temperature in degrees Celsius
• Day length in hours
• Year length in days
• Rings
• Habitable flag
• Canvas image of the planet

How to Use This Tool

1. Open the planet generator tool.
2. Select Planet Type from the menu.
3. Pick Random for a surprise planet.
4. Click Generate Planet to create a planet.
5. Review the stats and the image.
6. Change the type or click again for fresh results.

Picking a type builds a planet right away.

Inputs Explained

Select Planet Type

This drop down sets the base model for the planet.

• Random The tool picks any type from the list.
• Rocky Planet Small to mid size. Thin or none air. Zero to three moons.
• Gas Giant Very large size. Dense or helium rich air. Many moons and higher ring chance.
• Ice Giant Large cold body. Methane or helium rich air. Rings have a fair chance.
• Desert World Hot and dry surface. Thin or toxic air. Few moons.
• Ocean World Mostly water surface. Earth like or dense air. One to four moons.
• Jungle Planet Warm and wet surface. Earth like or dense air. One to three moons.
• Volcanic World Very hot surface with lava fields. Toxic or radioactive air. Few moons.
• Frozen Tundra Cold surface of ice and rock. Thin or methane air. Zero to five moons.

Generate Planet button

Click this button to create a new planet.

It works with any selection.

Use it again for another result.

Output Explained

Name

A random name built from short parts.

It may include a suffix or a number.

Type

The selected category or a random pick.

Diameter

Width at the equator in kilometers.

Type sets the range.

Gravity

Pull compared with Earth, shown as g.

The tool estimates it from size and a density factor.

A value of 1.00 g matches Earth gravity.

Atmosphere

A broad label for air type.

• None
• Thin
• Earth like
• Dense
• Toxic
• Radioactive
• Methane
• Helium rich

Moons

A whole number set by the type range.

Surface Temperature

Average surface value in degrees Celsius.

Ranges depend on type.

Day Length

Hours in one rotation.

Values range from 10 to 110 hours.

Year Length

Days in one orbit.

Values range from 50 to 5050 days.

Rings

Shows Yes or No.

Gas and Ice giants roll a ring more often.

Habitable

Shows Yes when these rules pass.

• Surface temperature stays between minus 50 and 60 Celsius.
• Air equals Earth like or Dense.
• Gravity sits between 0.5 g and 2.0 g.

Planet Image

A stylized planet on a square canvas.

Colors reflect the type.

Rings draw around the disc when present.

Tips for Better Results

• Try Random to spark new themes.
• Pick a type that fits your scene or quest.
• Click again to test many variants fast.
• Copy names you like into your notes.
• Use ringed giants for dramatic art or maps.
• Pick Jungle or Ocean for life friendly setups.

Limitations and Notes

• Traits come from ranges and simple rules.
• Gravity uses diameter to Earth ratio and a density factor.
• Day and year follow random ranges rather than a star model.
• The image is artistic and uses its own scale.
• Atmosphere labels give quick reading for air type.
• The habitable flag follows a simple check.
• Values change with each click.
• Units use kilometers and hours and days and degrees Celsius.
• Ring chance rises for Gas and Ice giants.
• Colors pick from a palette by type.

Example Use Cases

• Game design teams can sketch fast planet briefs.
• Tabletop groups can spin fresh settings between sessions.
• Writers can plan a new system with clear traits.
• Teachers can show scale and climate and orbit ideas in class.
• Concept artists can pull color and shape cues for scenes.

This planet generator keeps ideas flowing and saves time.

Use it for quick drafts or for deep worldbuilding sessions.

Pick a type, click once, and start building your setting.