How does the CS2 trade-up contract work?
Combine 10 skins of the same rarity tier to receive 1 skin from the next tier up. The output comes from any case that contains one of your input skins, and its float is determined by the weighted average of your inputs' normalized floats.
How many skins do I need for a trade-up?
Most tiers require exactly 10 skins. Covert (red) is the exception — only 5 Covert skins are needed for a chance at a knife or gloves.
How is the output float calculated?
CS2 uses this exact formula: average the normalized float of each input ((float − min) / (max − min)), then map that average onto the output's float range. CS2Lab uses the same formula — what you see here is what you'd get in-game.
What rarity tiers can be traded up?
Industrial Grade, Mil-Spec Grade, Restricted, Classified, and Covert. Consumer Grade skins cannot be used in trade-up contracts.
Can you profit from CS2 trade-up contracts?
Yes, but rarely. You need 10 input skins to cost less than the probability-weighted EV of all possible outputs. This calculator shows you profit chance and EV before you commit any skins.
Which cases give the best trade-up outputs?
Cases with expensive Classified or Covert skins — Kilowatt, Revolution, Dreams & Nightmares — tend to give the best EV. Use the case filter on the left to find the most profitable pool for your rarity tier.