Day 0
Select an item then click inside the jar to place it
Design a tiny world inside a glass jar. Layer soil, plants, decorations, and creatures. Watch your ecosystem come alive.
Terrarium Builder is a free browser-based creative game where you design a miniature ecosystem inside a glass jar. Choose from five jar shapes, then layer drainage material, soil types, plants, decorations, and tiny creatures to craft your perfect tiny world. Hit the time-lapse button to watch 30 days pass in 10 seconds — plants grow, moss spreads, and creatures wander around your creation.
The ecosystem health meter rewards compatible combinations: succulents love sandy soil, while ferns thrive in dark rich earth. Getting the balance right keeps your terrarium green and thriving.
Build your terrarium in layers — first add drainage (gravel or stones), then pick a soil type, then add plants from 20 options including ferns, succulents, mosses, mushrooms, and miniature trees. Decorate with tiny figurines and natural objects, then add up to three small creatures. Use the time-lapse to watch everything grow, or switch to Ambient mode for a calming living desktop scene. Export your creation as a PNG to share or save.
A terrarium is a sealed or open glass container that houses a miniature ecosystem of plants, soil, and sometimes small creatures. They were invented in 1842 by botanist Nathaniel Ward. A famous sealed terrarium built in 1960 by David Latimer is still thriving after 60+ years without being opened — the plants recycle their own water in a perpetual mini water cycle.
Closed terrariums thrive with moisture-loving plants like ferns, mosses, and tropical plants. Open terrariums are best for succulents, air plants, and cacti that prefer drier conditions. Mixing incompatible plants (e.g., succulents in a closed humid environment) causes rot and wilting. In this game, pairing succulents with sandy soil and mosses with dark earth gives you the best health score.
Closed terrariums create their own mini water cycle. Water evaporates from soil and plants through transpiration, condenses on the cool glass walls, and drips back down to the roots. This cycle repeats indefinitely, meaning a properly sealed terrarium never needs watering. Plants also recycle nutrients through the soil ecosystem, making them almost entirely self-sustaining.
Last updated: March 2026