CS2 cases: what an opening returns on average

How this figure is computed

The order: expected value minus the case price. For the same key price, that’s also the order of the average gain per opening, key deducted. A case with no expected value goes last.

Odds: the per-rarity rates published by Perfect World. Each rarity’s rate is split evenly across the case’s skins of that rarity, and the rare special item rate across each knife or pair of gloves, finish by finish. That’s the public convention for these rates.

StatTrak™: 10% of drops are the StatTrak™ version, when the case offers one. Gloves have none.

Wear: Valve doesn’t publish how float is rolled. We assume a uniform roll across each skin’s float range, and each wear gets the share of that range that falls within its bounds. It’s an assumption, not published data.

Prices: for each item, its cheapest listing, under the safeguards below. Buy prices, fees excluded.

Prices come from the quotes our search accepts: a stale quote, or one too far from the other marketplaces’ prices, is dropped. When an item has only two usable quotes and one is more than 5 times the other, nothing says which one is right. The median of Steam sales over the last 24 hours breaks the tie, if there was at least 1 sale: if only one of the two is less than 2 times away from that median, above or below, it’s kept and the other is dropped. Otherwise, both are dropped. The listing kept must then have at least 5 listings, at least 2 other marketplaces must list the same item, and from €1.00 up, its price must not fall below a third of their median: lower than that, it’s a suspect reading, not a deal. Under €1.00, a single cent is enough to swing that ratio, so this check doesn’t apply. Steam is never kept as the price: its credit can’t be withdrawn.

An item with no accepted price doesn’t count as 0: it’s left out of the average, and its odds are counted separately. Above 10% of drops without a price, there’s no expected value.

The key price is not measured: Valve only shows it in-game, and the third-party sources we read disagree. We don’t make it up, so there’s no total cost and no return.

Selling costs the marketplace’s fee: from 2% on CSFloat to 15% on Steam. What you’d get by reselling is therefore lower than these amounts.

Doppler and Gamma Doppler phases (Ruby, Sapphire, Emerald…) aren’t told apart: a Doppler knife counts at its cheapest listing, all phases together.

Source: “概率公示” page on csgo.com.cn, dated 11/09/2017, read on 29/09/2026.