CS2 Trade Up Calculator

How the CS2 Trade Up Calculator Works

A trade up contract takes 10 skins of the same rarity and returns one skin one rarity higher. The outputs are drawn from the collections of your inputs, so which skins you put in decides both the odds and the possible results.

The odds formula

Every input adds 1/10 of the weight to its own collection. The probability of any specific output skin is:

P(skin) = (inputs from its collection ÷ 10) × (1 ÷ outcomes in that collection)

That means a collection with fewer possible outputs concentrates the odds — the basis of most profitable trade-ups.

The float (wear) formula

CS2 changed this in October 2025. Each input float is normalized to its own range, the normalized values are averaged, and that average is mapped onto each output skin's own float range:

outputFloat = outMin + avgNorm × (outMax − outMin)

Because each output has different float caps, one contract can produce a Factory New for one outcome and a Field-Tested for another — so we compute the wear (and price) of every outcome individually. Buying low-float inputs pushes outputs toward Factory New, where high-rarity skins are worth the most. Pattern matters just as much as wear — a Case Hardened output can be an ordinary skin or a six-figure blue gem depending purely on its pattern index.

New to this? Start with our best cases to open guide and the CS2 case calculator, or compare the best CS2 trading sites to buy your inputs.

CS2 Knife Trade Up: How the Covert → Knife Contract Works

Since the October 22, 2025 update, you can finally trade up to a knife or gloves. The knife contract works differently from the standard one: it takes 5 Covert skins (not 10) and returns one knife or glove item. The game picks the output pool from the collections of your five inputs — put in five Coverts from the same caseand you guarantee that case's knife and glove pool; mix cases and the chance splits across them. StatTrak works too: five StatTrak Coverts return a StatTrak knife (gloves don't exist in StatTrak, so StatTrak contracts always produce knives).

The float math is the same normalized-average formula as regular contracts, so low-float Covert inputs push the knife toward Factory New. The market reality is worth knowing before you build one: the update sent Covert prices up and knife prices sharply down, and the economics keep shifting — which is exactly why the calculator prices every knife outcome from live market data rather than static lists. Select the Covert → Kniferarity in the tool and it switches to 5 input slots, showing each possible knife and glove with its odds, computed wear and current price. If you're weighing a contract against just buying the knife outright, check our knife price guide first.

Best CS2 Trade Ups: Finding Contracts That Actually Profit

Most trade ups lose money — the market prices inputs efficiently, and Steam's ~15% fee eats thin margins. The profitable minority almost always share three traits:

• Collection concentration. Outcomes come only from your input collections, so a single-collection contract into a collection with few, expensive outputs concentrates the odds where the value is.
• A float threshold play. Because the output float is the mapped average of your inputs, cheap low-float inputs can land outputs in Factory New range — often the biggest price jump between wears.
• A market price gap. The same skin can differ 10–30% between Steam, CSFloat and Buff163. A contract that loses on Steam prices can profit if you buy inputs and sell outputs on the right market.

You don't have to hunt these by hand: the profitable trade-up finder built into the calculator scans live prices and surfaces the contracts with positive expected value right now — the list changes daily as prices move. Treat even a +EV contract as a calculated risk, not an income source: expected value is an average across many contracts, and any single result can still be the cheap outcome.

Frequently Asked Questions