Best Free Simulation Games to Play in Your Browser

Simulation games are about making numbers go up — a city's population, a factory's output, a clicker's score, a tiny digital ecosystem's biodiversity. The browser is a surprisingly good home for them: they don't need cutting-edge graphics, they reward leaving a tab open, and most are perfectly happy to run for an hour while you read.

You'll find tycoon games (run a hotel, a zoo, a fast-food chain), idle clickers (the addictive kind where progress continues while you're not looking), city and farm builders, life-sim experiments, and a few weirder things — like games that simulate being a janitor, or running a bookshop, or surviving on a tiny rock in space.

All HTML5, all browser-based, all free. Most save your progress in browser storage so you can come back tomorrow and pick up where you left off. If you'd rather optimise a system than win a fight, this is the list.