Games like Growtopia
Games like Growtopia include Slime Rancher, Terraria, SPORE™, DAVE THE DIVER, and Trove. We matched them by the tags players give Growtopia on Steam (Casual, Adventure, Simulation, MMORPG, and Sandbox): closest matches first, and among equally close ones the better-known games.

Slime Rancher
Shared: Adventure · Exploration · Cute

Terraria
Shared: Sandbox · Adventure · 2D

SPORE™
Shared: Simulation · Sandbox · Casual

DAVE THE DIVER
Shared: Casual · Adventure · Exploration

Trove
Shared: MMORPG · Sandbox · Pixel Graphics

Disney Dreamlight Valley
Shared: Adventure · Simulation · Exploration

Starbound
Shared: Adventure · Sandbox · Casual

Totally Accurate Battle Simulator
Shared: Simulation · Sandbox · Adventure

Wobbly Life
Shared: Adventure · Simulation · Sandbox

Black Desert
Shared: Sandbox · MMORPG · Exploration

Hello Kitty Island Adventure
Shared: Adventure · Simulation · Casual

Garry's Mod
Shared: Sandbox · Casual · Simulation

Stardew Valley
Shared: Simulation · Pixel Graphics · Sandbox

Once Human
Shared: Exploration · Adventure · Simulation

Core Keeper
Shared: Exploration · Sandbox · Pixel Graphics

The Sims™ 4
Shared: Simulation · Sandbox · Casual

Planet Coaster
Shared: Simulation · Sandbox · Building

House Flipper
Shared: Simulation · Casual · Sandbox

The Elder Scrolls Online - Standard Edition
Shared: MMORPG · Adventure · Exploration

Two Point Museum
Shared: Casual · Simulation · Sandbox

Keplerth
Shared: Adventure · Sandbox · Exploration

Portal Knights
Shared: Adventure · Sandbox · Exploration

People Playground
Shared: Sandbox · Simulation · 2D