The drop ladder — same on every case
Counter-Strike's drop probabilities have been fixed since the introduction of weapon cases in 2013. Every case in our cases catalog uses these same odds, regardless of release year, operation tie-in or item pool:
| Tier | Probability | Rarity name |
|---|---|---|
| Mil-Spec | 79.92% | Blue |
| Restricted | 15.98% | Purple |
| Classified | 3.20% | Pink |
| Covert | 0.64% | Red |
| Rare Special | 0.26% | Gold (knives / gloves) |
On top of the rarity roll, each unboxed item has a separate ~10% chance to come out StatTrak™. So a "Covert + StatTrak" outcome sits at 0.064% — roughly 1 in 1,560 openings.
Wear is rolled too
After the rarity tier is decided, the game rolls a float value for the wear range. Float follows a uniform distribution within the skin's allowed range, so for a 0.00–1.00 float skin you'll see Battle-Scarred (0.45–1.00) roughly 55% of the time and Factory New (0.00–0.07) only 7%. Low-float drops are not "rare" — they're statistically frequent for FN-eligible skins, but visually cleaner floats command big premiums on the secondary market.
Expected value — the maths
Expected value (EV) of an opening = probability × average price of each tier, summed across tiers. For a case with average drop prices of:
- Mil-Spec: $0.20
- Restricted: $1.50
- Classified: $8.00
- Covert: $40.00
- Rare Special: $400.00
EV = (0.7992 × 0.20) + (0.1598 × 1.50) + (0.0320 × 8.00) + (0.0064 × 40.00) + (0.0026 × 400.00) = $0.16 + $0.24 + $0.26 + $0.26 + $1.04 = $1.96. Subtract the $2.49 key cost: -$0.53 net per opening. That's the median case experience — small loss, occasional jackpot, mostly Mil-Spec sticker drops worth less than a coffee.
Why retired cases beat the maths
When a case stops dropping (Operation Bravo, Glove Case, Operation Phoenix, eSports 2013 etc.) its supply is frozen but its skins keep appreciating. Over time the Covert and knife floor prices outrun the original-EV calculation. Operation Bravo Case currently trades for $20+ each on Steam Market — even at that key-inflated entry price, the EV from a $5,000+ knife floor can clear break-even on a long enough opening run.
Use the per-case "Unboxing economics" stats on our cases hub to see live expected drop value vs. key cost for every case in our catalog — including the retired ones flagged with the red badge.
Should you open cases?
Pure expected value says no for ~87% of active cases. That's the median case-opener experience: chasing a knife for 200 openings, ending up $400 down, getting it on opening 201 worth $300. The maths only flips in three scenarios:
- You only open retired cases that already trade above their original EV.
- You only open cases during a specific drop hype window (rare and short-lived).
- You target a specific knife / Covert and value the experience of opening (not the financial return).
If you want the skin and not the gamble, our live catalog shows the cheapest active marketplace listing for the same item — almost always for less than the expected number of cases you'd need to open.
Related reading
Want to see drop chances applied to a real case? Open any case page in the cases catalog — the "Drop chances" section breaks down probability per item and shows EV vs. key cost for that specific case. Or jump straight to the most popular ones: Recoil Case, Kilowatt Case, Fracture Case.