A CS2 Trade-Up Contract Analyzer, Not a Calculator That Guesses
CSAlpha finds and prices CS2 trade-up contracts — the recipe that converts ten same-rarity skins into one skin of the next rarity up — against real, currently-listed marketplace inventory, not average prices or assumed floats.
What CSAlpha Does
A trade-up contract's outcome is fully computable before you spend anything: which output skins are possible, how likely each one is, what wear (float) it lands on, and what it's actually worth. CSAlpha runs that computation continuously against real marketplace listings instead of once, on request, against assumed numbers. The core product is a live, ranked board of discovered contracts at /trade-ups, a free client-side calculator for pricing your own inputs before buying anything, and Blueprints, which prices theoretical contracts built from float-budget buy orders rather than listings that might sell before you can act on them.
Every number CSAlpha shows — expected value, ROI, best/worst case, chance to profit — is computed from the same underlying methodology described below, and the same math is exposed in full (with worked examples) in the guides section and the tips page.
How the Pricing & EV Methodology Works
Every trade-up has a set of possible output skins, determined by which collections the ten inputs came from — an output collection's odds are proportional to how many of the ten inputs belong to it, not split evenly across collections present. Each possible output's float is calculated, not guessed: each input's float is first normalized against that specific skin's own float range ((float − min) / (max − min)), the normalized values are averaged, and the average is projected onto the output skin's own float range. That float, in turn, determines which wear bucket — Factory New through Battle-Scarred — the output falls into, and wear buckets are where most of a trade-up's value sits, since price frequently jumps by a factor of two or more right at a wear boundary.
With every possible output identified, floated, and priced against real current listings, expected value is the probability-weighted sum of each outcome's net sell price, minus total input cost — net of marketplace fees on both sides of the trade (buying the inputs and selling the output), since those fees are frequently the difference between a contract that looks profitable and one that actually is. CSAlpha reports EV, ROI, best/worst case, and chance-to-profit together rather than a single headline percentage, because a contract's risk shape (a rare, large payout vs. a frequent, modest one) matters as much as its average outcome.
Data Sources
Listing and pricing data is drawn from three marketplaces: CSFloat, DMarket, and Skinport. CSFloat is the sole verification authority for whether an input is actually buyable — an input only counts as verified if a live CSFloat listing exists at the required float, deep-linked to the exact item. DMarket and Skinport listings contribute buy-side depth and price context but are not the verification gate. Each marketplace also charges its own buyer and seller fees, which are netted into every profit figure CSAlpha shows rather than left for the user to calculate separately — see the marketplace fees guide for the exact current rates.
Automatic Verification
Whether an input listing is genuinely available to buy is checked automatically in the background, not through a manual "verify" button a user has to click. This matters because marketplace inventory changes in real time — a listing that backed a contract's math a few minutes ago can sell before a user gets to it — so verification is treated as an ongoing process rather than a one-time check performed at discovery time.
Who CSAlpha Is For
- CS2 traders looking for trade-up contracts that are actually profitable once real listing prices, floats, and fees are accounted for — not theoretical ones that assume idealized inputs.
- Skin buyers and sellers who want to model a specific set of inputs before committing money, using the free calculator.
- Developers and analysts who need programmatic access to float-accurate pricing and market signals, via the Developer API.
- Newcomers to trade-ups who want to understand the mechanics before risking anything — start with the beginner's guide.