CS2 Trade Up Guide

Trade up contracts let you exchange lower-rarity skins for a chance at higher-tier items, up to and including knives and gloves. This page covers how they work, the float calculation formula, collection stacking, and Doppler phase odds. If you want to test a specific trade up, use the trade up calculator.

How Trade Ups Work

A trade up contract takes 10 items of the same rarity and returns 1 item of the next rarity tier. The output is randomly selected from the next tier across all collections represented in your inputs. Each input item's collection contributes possible outputs, so the more items from a single collection, the higher the chance of getting an output from that collection.

Trade ups work the same way in CS2 as they did in CS:GO. The items are consumed permanently, so run the numbers in the trade up calculator before committing real skins.

Rarity Upgrade Path

Each trade up moves you one tier up the rarity ladder. The final step (Covert to knives/gloves) is a special case that only requires 5 inputs.

Gold Trade Ups / Knife Trade Ups

The most sought-after trade ups in CS2 are gold trade ups , also called knife trade ups or glove trade ups. These use Covert (red) items as inputs and output knives or gloves from the Rare Special (gold) tier.

Unlike standard trade ups, you only need 5 Covert items instead of 10. The outputs come from a flat pool of all knives and gloves, so your input collections don't affect which ones you can get. Covert inputs are expensive, but a single knife can be worth many times your input cost.

Since collections don't matter for gold trade ups, it comes down to minimizing input cost and targeting a good output float. Use the trade up calculator to see every possible knife and glove output with exact probabilities.

Float Calculation

The output float is determined by your input floats, not random. CS2 uses a 3-step formula:

1. 1Normalize — Each input float is normalized to a 0–1 scale based on that item's float range: (float - minFloat) / (maxFloat - minFloat)
2. 2Average — The normalized values are averaged across all inputs
3. 3Map to output range — The average is mapped to the output item's float range: outputFloat = (outputMax - outputMin) × avgNormalized + outputMin

Practical example: If you feed 10 Factory New AK-47 Redlines (float range 0.10–0.70) each at 0.10 float, the normalized average is 0.0 (the lowest possible). An output skin with range 0.00–0.50 would get a 0.00 float (Factory New). An output with range 0.06–0.80 would get 0.06, still Factory New but higher. The output item's own float range is what determines the final wear condition.

StatTrak Trade Ups

StatTrak trade ups follow the same rules with one strict requirement: all inputs must be StatTrak. You cannot mix StatTrak and non-StatTrak items. The output will always be StatTrak.

StatTrak skins have separate pricing on the market, usually higher than normal versions. The price gap between input and output tiers is often larger for StatTrak items, which can make these trade ups more profitable. Toggle StatTrak mode in the trade up calculator to compare EV between normal and StatTrak trade ups.

Collection Stacking

Collection stacking is the core strategy for standard trade ups (Consumer through Classified). Each input item contributes its collection to the output pool. The probability of getting an output from a specific collection is proportional to how many of your inputs belong to that collection.

Example: If you put in 8 items from The Mirage Collection and 2 from The Dust 2 Collection, you have an 80% chance of getting a Mirage Collection output and a 20% chance of a Dust 2 Collection output. If the Mirage Collection has a high-value skin at the next tier, stacking 8/10 inputs from it maximizes your odds.

This doesn't apply to Covert (gold) trade ups. Knife and glove outputs come from a shared pool regardless of input collections.

Doppler Phase Weighting

When a trade up can produce a Doppler or Gamma Doppler knife, the phase is not equally distributed. The rare patterns have much lower odds:

• Ruby — ~1%
• Sapphire — ~1%
• Black Pearl — ~1%
• Emerald — ~1% (Gamma Doppler only)
• Phase 1–4 — split remaining ~96% (~24% each)

The trade up calculator factors in these phase weights when computing probabilities and expected value.

Finding Profitable Trade Ups

A trade up is profitable when the expected value (EV) exceeds your total input cost. EV is calculated by multiplying each possible output's price by its probability, then summing all outcomes.

The trade up calculator shows Expected Value (average return over many trade ups), Chance to Profit (percentage of outcomes worth more than your input), and Expected Profit (EV minus input cost). A trade up can have positive EV but low profit chance if it depends on hitting one expensive output.

Good trade ups tend to come from collections where the next tier has a big price spread. Stack your inputs toward the collection with the expensive skin. Prices come from Steam Community Market and CSFloat, updated every 6 hours. See CS2 drop rates for how rarity affects the skin economy.