CS2 Trade-Up Calculator

You hand over 10 skins of one rarity and receive 1 skin of the next rarity, drawn from the collections of your inputs. The game first picks one of the 10 inputs at random, then draws uniformly from that collection’s next-tier skins, so P(outcome) = inputs from its collection / 10 × 1 / next-tier skins in it. Consumer Grade and Contraband items cannot be used, and StatTrak never mixes with normal. Full rules with a worked example: Full trade-up guide: odds, float math and a real profit check

The output float is deterministic: each input float is normalized within that skin’s own range ((float − min) / (max − min)), the ten values are averaged, and the average is mapped onto the outcome’s range. A Factory New copy of a skin capped at 0.40 normalizes to a much higher value, so contracts built from “expensive FN” inputs routinely produce Minimal Wear outputs. The calculator applies exactly this formula and lets you edit every input float.

The board scans every single-collection contract: 10 copies of the cheapest input skin per collection, rarity and wear, requiring at least 10 offers at the cheapest venue. Input floats are assumed at the middle of the wear bracket, outcomes are valued at their cheapest fee-included ask quoted on at least 2 markets. It is a snapshot ranking, not a guarantee: asks move, thin listings sell out, and a sale nets less than the ask after the venue seller fee. Positive EV pays off across many contracts, never a single one.

Since October 2025, five Covert skins can be traded up to one Exceedingly Rare item (knife or gloves) from an input collection; since May 2026, souvenir skins are valid inputs and lose their souvenir attributes. This calculator covers standard 10-input contracts; the knife contract math and both rule changes are measured in the guide below. In Russian community slang the mechanic is also called трейд-ап or крафт.