Valve publishes the odds for CS2 cases. Most players have never read them. Here they are, and here is what they mean once you work them through, because the published percentages are considerably less reassuring than they first appear.
The Published Numbers
Every standard case uses the same rarity distribution:
Mil-Spec, the blue tier, at 79.92 percent. Restricted, purple, at 15.98 percent. Classified, pink, at 3.20 percent. Covert, red, at 0.64 percent. Rare Special Items — knives and gloves, the gold tier — at approximately 0.26 percent.
Four openings in five produce a blue. That is the honest headline.
What 0.26 Percent Looks Like in Practice
A one in 385 chance sounds survivable until you extend it.
Open 100 cases and your chance of seeing at least one knife is around 23 percent. Open 265 and you reach roughly even odds — this is the median, the point at which half of players have hit one and half have not. Open 1,000 and around 7 percent of players still will not have seen a gold.
That last figure is the one worth sitting with. Seven in every hundred people who open a thousand cases get nothing from the gold tier at all. Each opening is independent; the game does not owe you anything for the previous 999.
The Cost Side
Keys cost $2.49 each and that price does not vary. Cases themselves range from a few cents for active-pool containers to well over a hundred dollars for discontinued ones.
Take a cheap case at 20 cents. Two hundred and sixty-five openings — the median to a knife — costs about $713 in keys alone, plus $53 in cases. You reach the halfway point of the knife distribution having spent over $750.
Whether that is good value depends entirely on what the knife is worth, and since October 2025, when Valve made knives craftable through trade-up contracts, knives are worth substantially less than they used to be.
Expected Value
Multiply each tier’s probability by the average market value of its contents, add them up, and you get the expected return on one opening. Subtract the cost of the case and key.
For virtually every case in the game, that number is negative. This is not a flaw or a secret; it is the design. The system funds itself through the gap between what openings cost and what they return.
A handful of discontinued cases show better ratios because their contents have appreciated faster than their price, but “less negative” is not the same as positive, and the cases themselves cost more to acquire.
Free Cases
You receive two free cases a week by playing, drawn from the active pool. These change the arithmetic meaningfully, because the case is free and only the key is a cost.
It does not change the odds. A free case has exactly the same 0.26 percent as a purchased one. It just removes one of the two expenses.
What to Take From This
Open cases if you enjoy opening cases. The animation, the anticipation and the occasional good result are entertainment, and entertainment is allowed to cost money.
What does not survive contact with the numbers is treating it as a way to make money. That applies to Steam openings and equally to third-party formats such as CS2 Case Battles, all of which operate with a margin built in. Set a figure you are content to lose, treat anything that comes back as a bonus, and never chase a loss across a session.
The odds are published precisely so you can make that decision informed. Very few people read them, which is the only genuinely surprising thing about any of this.