A simulator makes up its own stock market. That one fact decides what it can teach you.
A stock market simulator is a program that makes up a whole stock market. It invents the companies. It invents their share prices. It invents the economy around them. Then it lets you buy and sell, with money that was never real.
Nothing you do here touches a real stock exchange. No real shares move.
People mix this up with two other things. A paper trading account uses real, live prices from the real market. It just doesn't send your orders anywhere. A broker's demo account does the same thing on the broker's own screens. A simulator goes further back and builds the market itself.
Real data only gives you one story, and you already know how it ends. Practise on the last six months and you're trading a stretch of time you could just look up. Proper crashes turn up maybe once a decade. You'd have to sit and wait for one.
A made-up market runs as fast as you like. You can restart it. You can ask it for a crash. One run of Margin Call covers about five years and fits into an evening. So you can live through a whole run of rising interest rates tonight, then go again tomorrow knowing more.
The catch? A made-up market is only as good as the maths behind it. So ask about the maths. Most simulators do badly here.
The lazy version nudges every price by a random amount, adds a slow drift upward, and calls that a market. The chart looks convincing. You'll learn nothing from it, because there's nothing under the price to think about. Nobody outsmarts a dice roll, so any skill you think you're building is superstition.
A good model makes prices happen for reasons. In Margin Call every company has a fair value, worked out from its profits and from interest rates. The price you trade at is that fair value, knocked off course. The knock fades away over about sixty days. So a share can be too dear, it won't stay too dear forever, and you get to have an opinion about it.
It can't teach you how it feels to lose money you needed. Traders all say the feelings are the hard part, and no simulation hands you those. Betting big is easy in a browser tab. It's much harder when the rent depends on it.
It can't teach you the small print of a real market either. How your broker handles an order. What one company puts in its results. Those are facts about the real world, and a made-up market doesn't have them.
What it does teach you is how things work. Why a company with big debts falls harder when rates go up. What happens when everyone's stop-loss sits at the same price. That carries over, because it's true of markets in general.
Margin Call is free, runs in a browser, and needs no account. It has 108 companies across 12 sectors, plus options, crypto, bonds, currencies and prediction markets. All of it sits inside an economy with its own inflation, unemployment, interest rates and boom-and-bust cycles.
Margin Call is a game. It has no link to any broker or any real market, and nothing in it is financial advice. You get to be wrong here for free.