CS2 Trade Up Contracts Explained
A Trade Up Contract is Counter-Strike 2's built-in way of turning ten skins you do not want into one skin from the next rarity tier up. It is the only mechanic in the official client that lets you change what is in your inventory without buying, selling or opening anything — and it is the one most people get wrong, because the rules about rarity, collections and float are strict and completely unforgiving once you hit the confirm button.
This guide covers what the contract actually does, the five rules that decide whether it will even let you submit, how the output float is calculated, and how the Contract feature on DuckSkins differs from Valve's version — because the two share a name and almost nothing else.
What a Trade Up Contract Does
You put in ten skins of the same rarity and get back one skin of the next rarity up. The ten are consumed. There is no refund, no preview of the result, and no way to cancel once it runs.
The tiers step upward in this order, and the contract can move you one step at a time:
- Consumer Grade (white) → Industrial Grade (light blue)
- Industrial Grade → Mil-Spec (blue)
- Mil-Spec → Restricted (purple)
- Restricted → Classified (pink)
- Classified → Covert (red)
Covert is the ceiling. You cannot trade up Covert skins, and there is no route to the Rare Special tier — knives and gloves are outside the contract system entirely. Anyone telling you they trade-upped into a knife is describing something that the official client does not do.
The Five Rules
1. Exactly ten inputs
Not nine, not eleven. The contract will not submit until all ten slots are filled.
2. All the same rarity
Ten Mil-Spec skins, or ten Restricted skins. You cannot mix tiers to "top up" a contract with something cheaper.
3. All the same quality
Ten normal skins, or ten StatTrak™ skins. Mixing the two is not allowed. Ten StatTrak™ inputs produce a StatTrak™ output, with its counter reset to zero.
4. No Souvenir skins
Souvenir items are excluded from the contract system regardless of their rarity.
5. No trade-locked items
A skin still inside its trade hold cannot be used as an input until the hold expires.
Where the Output Comes From
This is the part that decides everything, and it is the part most guides skip. The output is not drawn from "all skins of the next tier". It is drawn from the collections your ten inputs came from, and each collection's share of the output pool is proportional to how many of your ten inputs came from it.
Put ten Mil-Spec skins from a single collection in, and every possible output is a Restricted skin from that same collection. Put in five from one collection and five from another, and the two collections split the pool evenly. This is why people build contracts entirely from one collection: it is the only way to control what can come out.
A collection with a small number of skins at the tier above gives you a narrow, predictable output pool. A collection with many gives you a wide one. Neither is better in the abstract — it depends entirely on which skins are in the pool and what they are worth.
How the Float Is Calculated
The output's float value is not random. It is derived from the average float of your ten inputs, mapped onto the output skin's own float range:
output float = (output max − output min) × average input float + output min
Two consequences follow, and they are the whole of trade-up float strategy:
- Lower input floats produce a lower output float. Ten Factory New inputs with an average float of 0.02 will land near the bottom of the output's range.
- The output's own range caps what is possible. Many skins do not use the full 0.00–1.00 range. A skin whose range starts at 0.10 can never be Factory New, no matter how pristine your inputs were. Checking the output pool's float ranges before you commit is the difference between a planned contract and a hopeful one.
What a Trade Up Cannot Do
It cannot produce a knife or gloves. It cannot skip a tier. It cannot be undone. And it does not guarantee the output is worth more than the inputs — a Restricted skin from an unpopular collection can be worth less than the ten Mil-Spec skins you fed into it. The contract changes what you hold; it makes no promise about what that is worth.
How the DuckSkins Contract Is Different
Contract on DuckSkins shares a name with Valve's mechanic and works on a completely different basis. It is worth being precise about, because the two are easy to confuse:
| Valve Trade Up Contract | DuckSkins Contract | |
|---|---|---|
| Inputs | Exactly 10, same rarity, same quality | Any 3 to 10 skins, any rarity, any mix |
| What decides the output | Rarity tier and the inputs' collections | The combined value of what you put in |
| Output range | One skin from the next rarity tier | One skin worth 75% to 125% of the combined value |
| Shown before you commit | Output pool only | The minimum and maximum you can receive |
| Verifiable afterwards | No | Yes — provably fair |
The important line in that table is the third one. The DuckSkins Contract is a reroll around what you put in, not a step up from it. The result can come back worth less than the skins you submitted, and the page tells you the floor and the ceiling before you confirm. The roll itself is committed in advance and can be checked afterwards with your own client seed, which Valve's contract offers no equivalent of.
Frequently Asked Questions
Can you trade up to a knife in CS2?
No. Knives and gloves sit in the Rare Special tier, which is outside the contract system. Covert is the highest tier a trade up can produce.
Do all ten skins have to be from the same collection?
No, but each collection's share of the output pool matches its share of your inputs. Using one collection is the only way to know exactly which skins can come out.
Can a trade up lose value?
Yes. A higher rarity tier does not guarantee a higher price — an unpopular Restricted skin can be worth less than the ten Mil-Spec skins that produced it.
Does StatTrak carry through a trade up?
Yes, but only if all ten inputs are StatTrak™. The output is StatTrak™ with its kill counter reset to zero. Mixing StatTrak™ and normal skins is not allowed.
How is the DuckSkins Contract different from a trade up?
It takes 3 to 10 skins instead of exactly ten, ignores rarity entirely, and returns one skin worth between 75% and 125% of their combined value. You see that range before you commit, and you can verify the roll afterwards on the Provably Fair page.
See Every Drop Chance Before You Open
On DuckSkins every case lists its full contents and the listed drop chance of every skin on the case page itself, before you open and without signing in. Combine skins on the Contract page, open CS2 case battles against other players, or read the CS2 case opening guide to see how the whole thing works.