Complete CS2 Trade Up Contract Guide 2026

I got into trade-ups around 2016 and lost money on my first few because I didn't understand how the float formula worked. I was just throwing 10 cheap skins in, hoping something valuable came out. It took a while to realize there's actual math behind all of this - and once you understand it, trade-ups stop feeling like gambling and start feeling like a system you can work. This guide covers everything I know now that I wish I'd known then. It's also the reason CS2Locker's trade-up calculator exists.

What is a Trade Up Contract?

A trade-up contract lets you exchange exactly 10 skins of the same rarity for one skin of the next rarity tier. The output skin is random - but which skins can appear depends entirely on which collections your 10 inputs belong to. That's the lever you control.

If you do the math beforehand, you can find combinations where the expected output value is higher than what you put in. That's the whole game. The people who make consistent money from trade-ups aren't lucky - they've simply calculated whether the deal is positive or negative before committing.

Rarity Progression in CS2

Every rarity tier feeds into the one above it. Here's the full chain:

• Consumer Grade (White) → Industrial Grade (Light Blue) (10 inputs)
• Industrial Grade (Light Blue) → Mil-Spec (Blue) (10 inputs)
• Mil-Spec (Blue) → Restricted (Purple) (10 inputs)
• Restricted (Purple) → Classified (Pink) (10 inputs)
• Classified (Pink) → Covert (Red) (10 inputs)
• Covert (Red) → Knives & Gloves (Gold) (5 inputs)

One important note: Contraband skins like the M4A4 Howl cannot be used as trade-up inputs and cannot be obtained through trade-ups. They exist outside the system entirely.

The Float Value Formula - The Part Most People Skip

Every skin has a float value between 0 and 1 that determines its wear condition and often has a dramatic effect on price. If you do a trade-up without understanding this formula, you will frequently produce lower-condition outputs than you expected - and that difference in float can mean hundreds of dollars on high-value skins. Here is how it works:

The three variables are straightforward: your average input float is just the sum of all 10 floats divided by 10. Min and Max are the minimum and maximum possible float values of the output skin - these are fixed per skin and you can look them up before you trade.

A Practical Example

Say you're trading up to an AWP Asiimov, which has a float range of 0.18 to 1.00. Your 10 input skins have an average float of 0.10. The math gives you: (0.10 × 0.82) + 0.18 = 0.262. That means you'll get a Field-Tested Asiimov with a float of 0.262 - not a Minimal Wear, not a Battle-Scarred. Exactly 0.262, every time. No variance. You can know the output condition before you commit.

This is what separates informed traders from everyone else. By choosing your input floats carefully, you can aim for specific output conditions. A Factory New output with a 0.04 float is worth considerably more than one sitting at 0.06 - and the difference comes entirely from the floats you chose to put in.

How Outcome Probability Works

Each input skin contributes a 10% chance toward the output pool. The probability of receiving any specific output skin is determined by how many of your 10 inputs share its collection. If you put in 6 skins from Collection A and 4 from Collection B, you have a 60% chance of getting Collection A's higher-tier skin and a 40% chance of getting Collection B's. Stack all 10 inputs from the same collection, and you guarantee a specific output pool - though those inputs usually cost more as a result. This is the core tradeoff in every trade-up decision.

How to Find a Profitable Trade Up

A trade-up is profitable when the Expected Value (EV) of all possible outputs - weighted by their probability - exceeds what you paid for the inputs. The calculation isn't complicated once you've done it a few times. Add up the cost of your 10 inputs. Identify every skin you could receive and what each is worth. Multiply each outcome's value by its probability of occurring and sum everything together. If that number is higher than your input cost, after accounting for marketplace fees, the trade-up has positive EV. If it's lower, you're statistically expected to lose money - even if you occasionally get lucky.

The CS2Locker trade-up calculator handles all of this automatically. You won't need to do this by hand every time.

Best Collections for Trade Ups in 2026

The best trade-up opportunities come from collections where there's a significant price gap between the rarity you're inputting and the rarity you're targeting. A collection where Classified skins are worth $5 and Covert skins are worth $200 is more interesting than one where both tiers are worth similar amounts.

Top Tier Collections

The Cobblestone Collection is the home of the AWP Dragon Lore - one of the most valuable skins in the game - making it a high-stakes trade-up destination for those who can afford the inputs. The Bravo Collection holds the AK-47 Fire Serpent, a discontinued covert skin whose price has only gone up as supply shrinks over time. The Overpass Collection offers the M4A1-S Master Piece, and Gods and Monsters is where the AWP Medusa lives - both collections with dramatic rarity price gaps worth exploring.

Budget-Friendly Collections

If you're just getting started, the Chroma Collections offer solid value at lower price points and are heavily traded, which means inputs are easy to find. The Prisma Collection is probably the most accessible entry point for beginners - cheap inputs, decent spread between tiers, and high market volume so you can buy and sell quickly without moving the price.

Covert to Knife/Glove Trade Ups

Since October 2025, you can trade up 5 Covert (Red) skins to receive a Knife or Glove from one of the cases your inputs belong to. This is a genuinely significant change. Only 5 inputs are required instead of 10, and the outputs are the most sought-after items in CS2. Your inputs must come from cases that contain gold-tier items - collection skins without knives or gloves won't work here. StatTrak inputs produce a StatTrak knife. And the float formula still applies, which means low-float inputs can land you a better-condition knife.

Best Cases for Covert Trade Ups

The Chroma Cases give access to Doppler knives including Ruby, Sapphire, and Black Pearl - the rarest Doppler phases. The Spectrum Cases feature Marble Fade and Doppler finishes. The Glove Case is the obvious choice if you want Sport Gloves. Operation Cases sometimes have cheaper Covert inputs, making the math work out better even when the potential outputs are similar.

StatTrak™ Trade Ups

StatTrak trade-ups follow a separate but simple rule: all 10 inputs must be StatTrak, and the output will always be StatTrak. You cannot mix StatTrak and non-StatTrak inputs. The premium for StatTrak outputs can be substantial on popular skins, which means a successful StatTrak trade-up sometimes pays significantly better than the non-StatTrak equivalent - but the inputs cost more too, so the risk is higher in absolute terms. Covert StatTrak trade-ups follow the same logic: 5 StatTrak Covert inputs yield a StatTrak knife.

Mistakes That Cost People Money

The biggest one is not calculating EV before committing. The second is ignoring float values and ending up with a lower-condition output than expected - which can cut your profit in half on high-value skins. Steam's 15% marketplace fee gets overlooked constantly; what looks like a $10 profit becomes a loss once you factor it in. Emotional trading - chasing a loss from a bad trade-up with another trade-up - is how people dig themselves into holes. And using stale price data is a real problem in a market that moves daily. Always check current prices before you execute.

Advanced Strategies Worth Knowing

Float Targeting

Since the output float is deterministic, you can work backwards from the condition you want and choose your inputs accordingly. A Factory New output at 0.02 float sells for considerably more than one at 0.06, and the inputs to achieve that are often the same price. Float targeting is one of the highest-leverage skills in trade-ups.

Collection Stacking

Putting all 10 inputs from the same collection gives you a 100% chance at a specific output pool - no split probability, no unwanted outcomes. The inputs tend to cost more as a result, but the predictability has real value, especially when you're targeting a specific skin in a collection with only one viable covert output.

Marketplace Arbitrage

The same skin can be listed at meaningfully different prices across different platforms. Buying inputs where they're cheapest and selling outputs where they command the highest price is a legitimate edge - especially on high-volume skins where the spread is consistent. CS2Locker's price comparison shows all platform prices side by side so you don't have to check manually.

Try the CS2Locker Trade Up Calculator

The calculator handles the EV math, the float formula, and probability calculations automatically. Forward mode lets you pick your inputs and see every possible output with its probability and expected value. Reverse mode lets you pick the skin you want and find the cheapest input combination to get there. Give it a try - it changes how you think about trade-ups entirely.