A CS2 weapon case is a container you open with a separate key to receive one random skin from its own fixed list. The key is a separate purchase, and every case in the game uses the same rarity distribution, so the odds are identical no matter which case you open. Since mid 2026 the opening screen also offers a second option: open the case to rent its contents for a week instead of keeping one skin.
What a weapon case is
A weapon case is a tradable item that holds a set list of skins. You open it with a key, and the game picks one skin from that list. The CS2 wiki's case index runs from the CS:GO Weapon Case in 2013 through the Gallery Case in 2025, and every case in that list has a rare chance of containing a knife or glove skin.
The two options at the opening screen
Valve's own Steam Support article for CS2 weapon rentals describes the choice you get when you open a case: Open to Keep or Open to Rent. Choosing Open to Rent consumes both the case and the key, and every weapon in the case except the exceedingly rare item is added to your in-game inventory. Rented weapons can be equipped and played with in all game modes.
Rentals last one week. When the week ends, a rented weapon still equipped in your loadout is replaced with the stock version of that weapon. Valve states that rented weapons cannot be modified in any way, which means no stickers and no Name Tags, and they cannot have StatTrak. The wear rating on a rented weapon is randomised and can range from Factory New to Battle Scarred. Rentals are not refundable, because the case and key are consumed when you rent, and Valve states that rented weapons are not and will not be visible in your CS2 inventory on Steam. You can check the time left on a rental in your in-game inventory.
The rarity tiers and the drop odds
Every CS2 weapon case uses a fixed probability distribution to decide which rarity tier your drop falls into, and those percentages are the same across all cases. The published figures are:
- Mil-Spec, blue: 79.92 percent, roughly 1 in 1.25 openings
- Restricted, purple: 15.98 percent, roughly 1 in 6.3
- Classified, pink: 3.20 percent, roughly 1 in 31
- Covert, red: 0.64 percent, roughly 1 in 156
- Exceedingly Rare, gold: 0.26 percent, roughly 1 in 385
StatTrak is a separate roll. About 10 percent of all case drops carry the StatTrak attribute, and that 10 percent applies evenly across every rarity tier. A StatTrak blue is therefore about 7.99 percent of openings and a StatTrak knife about 0.026 percent.
Float and wear
The float value of a dropped skin is generated randomly inside the skin's allowed range when it comes out of the case. Most skins accept the full 0.00 to 1.00 range, but some are restricted. SteamAnalyst uses the AWP Asiimov as an example: it can only drop with floats between 0.18 and 1.00, so it never arrives in Factory New or Minimal Wear. A lower float means less visible scratching and usually a higher price.
What this means for your wallet
SteamAnalyst's case by case ranking prices each case against what it drops and finds that every case has a negative expected return, with average losses per opening ranging from about 32 to 74 percent depending on the case. Older discontinued cases with expensive pools lose least, while the cheaper current cases often lose most. The practical reading is simple: if you want a specific skin, buying it outright is cheaper than opening cases to chase it. Treat case opening as entertainment with a known cost, not as a way to make items.
Frequently asked questions
- Do different cases have different odds? No. The rarity percentages are identical across every CS2 weapon case. Only the skin list inside each case changes.
- Can I rent a knife or glove? No. Valve states that Open to Rent adds all weapons in the case minus the exceedingly rare item, so the gold tier is excluded from rentals.
- Do rented weapons show on my Steam inventory page? No. Valve states rented weapons are not visible in your CS2 inventory on Steam.
- Can I sell a rented weapon? No. Valve states rented weapons cannot be modified, and the case and key are consumed, so there is nothing to return or sell. They expire after one week and are replaced with the stock version.
- Is StatTrak better odds on rare items? No. StatTrak is its own 10 percent roll on top of the rarity roll, so it is proportionally rarer on rare items, not more common.
- Do I need a key to rent? Yes. Valve states the key and case are consumed either way, so renting costs the same key purchase as opening to keep.
- How long does a rental last? One week, or 7 days. At the end of the week, equipped rented weapons are replaced with the stock version.
CS2 Wiki: Weapon Cases
Steam Support: CS2 weapon rentals
SteamAnalyst: CS2 case odds and drop rates