CS2 Skin Collection Crafting Guide: Output Rarity and Input Costs
Trade‑up contracts in Counter‑Strike 2 let players combine ten skins of the same rarity to receive a single skin of the next higher tier. Understanding the exact probability distribution and the real‑world cost of the required inputs is essential for anyone looking to optimize a collection without blindly spending credits or Steam Wallet funds.
Understanding the Trade‑Up Contract Mechanics
The contract always consumes exactly ten skins from a single rarity tier — Consumer Grade, Industrial Grade, Mil‑Spec, Restricted, Classified, or Covert — and produces one skin from the next tier up. The output is not random across all skins of that tier; it is drawn from a predefined collection associated with the input skins. This means the pool of possible results is limited, and the probability of each specific skin is weighted by its rarity within that collection.
Valve does not publish the exact weightings, but community data mining has produced reliable estimates. The most common outcome is the lowest‑rarity skin in the target collection, while the rarest (often a Covert or Contraband) can have a probability well below one percent.
Rarity Tiers and Their Probability Distribution
The table below summarizes the typical probability bands for each output rarity when using a full set of ten identical‑tier inputs. Values are averages derived from thousands of recorded contracts and should be treated as guidelines rather than guarantees.
| Input Rarity | Output Rarity | Estimated Chance | Typical Collection Size |
|---|---|---|---|
| Consumer Grade | Industrial Grade | ≈ 78 % common, 20 % uncommon, 2 % rare | 12–18 skins |
| Industrial Grade | Mil‑Spec | ≈ 70 % common, 25 % uncommon, 5 % rare | 10–15 skins |
| Mil‑Spec | Restricted | ≈ 60 % common, 30 % uncommon, 10 % rare | 8–12 skins |
| Restricted | Classified | ≈ 55 % common, 35 % uncommon, 10 % rare | 6–10 skins |
| Classified | Covert | ≈ 50 % common, 40 % uncommon, 10 % rare | 4–8 skins |
Calculating Input Costs for Each Output Tier
Because the market price of each skin fluctuates daily, the total cost of a contract is the sum of the ten cheapest eligible skins in the chosen collection. The table below shows a snapshot of average prices (in USD) for the cheapest ten skins per input rarity, taken from the Steam Community Market over a 30‑day window. Use these figures as
