Game engines can be either free or paid. The cost depends on the specific engine, its features, and licensing conditions.
Free Game Engines: Some game engines are completely free to use, such as Unity (for revenues under $100K per year), Godot, and Unreal Engine (royalties apply after a certain revenue threshold). These engines might offer paid versions that provide additional services or support.
Unity is free for individuals and small companies that have less than $100K in annual gross revenues during the most recent fiscal year.
Unreal Engine Example
Unreal Engine is free to use, but Epic Games collects a 5% royalty on gross product revenue after the first $1,000,000 per game per calendar quarter.
Paid Game Engines: Some game engines require you to pay upfront or subscribe to a license. Examples include CRYENGINE (pay what you want model), and GameMaker Studio 2 (different tiered pricing models).
In addition, some game engines may require a percentage of your game's revenue once it surpasses a certain threshold. Always be sure to carefully read the terms and conditions before choosing an engine for your game development project.