Trade-up contracts changed more in the last year than in the decade before. The October 2025 update added knife and glove trade-ups and, alongside them, a new way of working out odds and floats. Valve's patch notes only announced the knife and glove rules; the odds and float changes were worked out by traders from contract results and are documented in community guides (see sources). Many guides and older calculators still describe the old rules. This page explains the current ones, works through a real example with float ranges checked against the game files, and then looks at what TradeUpLab and other calculators do.
How trade-up contracts work now
- Regular contracts: 10 skins of the same rarity give 1 skin of the next rarity, from Consumer Grade inputs up to Classified inputs that give a Covert.
- Covert contracts: 5 Covert skins give 1 knife or 1 pair of gloves (more on this below).
- StatTrak: all inputs must be StatTrak or all must be normal. StatTrak inputs give a StatTrak output.
- Souvenir: since a May 2026 update, Souvenir skins can be used alongside normal ones. Their Souvenir attributes are removed, and the result is always a normal item.
- Eligibility: a skin can only go in if its collection has something one rarity higher. A skin from the top tier of its collection cannot be used, unless it is a Covert whose collection has knives or gloves.
The output always comes from a collection of one of the skins you put in. That is the whole game: choose inputs from collections whose next-tier skins are worth more than the inputs cost.
How the odds work
Under the current rules, every input is one equal ticket:
- Chance of a collection = inputs from that collection ÷ total inputs (10, or 5 for Covert contracts)
- Chance of a specific skin = that collection's chance ÷ the number of next-rarity skins in that collection
According to community testing (Valve did not announce this part), before the October 2025 update the number of possible outputs in each collection also changed the weighting, which let traders use cheap "filler" skins to steer the odds. That trick no longer works. A single input from a collection now carries exactly 10% of a regular contract, however many outputs that collection has.
The float formula
Every skin has a float between 0 and 1 that sets its wear: Factory New below 0.07, Minimal Wear to 0.15, Field-Tested to 0.38, Well-Worn to 0.45 and Battle-Scarred above that. Many skins only exist in part of that range. The AUG | Death by Puppy, for example, runs from 0 to 0.40.
The current formula has three steps:
- Normalize each input inside its own range: (input float − input min) ÷ (input max − input min).
- Average the normalized values across all inputs.
- Map the average into each output's range: output float = output min + average × (output max − output min).
The old formula skipped step 1 and averaged raw floats. That difference matters most for inputs with a narrow range. A 0.10 float on a skin that only goes up to 0.72 sits about 14% of the way through its range, not 10%, so it now counts as slightly more worn than its raw number suggests.
Covert to knife or gloves
Valve's October 22, 2025 patch notes extended the Trade Up Contract with two rules:
- 5 StatTrak Covert skins give one StatTrak knife from a collection of one of the inputs.
- 5 normal Covert skins give one normal knife or one pair of gloves from a collection of one of the inputs.
What follows from that:
- Each Covert input is worth 20% of the odds, because there are only five. The same float formula applies, with five inputs instead of ten.
- StatTrak gloves do not exist, so StatTrak Coverts from cases whose rare items are gloves only (the Glove Case and Revolution Case, for example) cannot be used.
- Coverts from collections with no knives or gloves cannot be used either. The AWP | Dragon Lore from the Cobblestone Collection is the best-known example.
- Knife and Covert prices moved sharply when the update landed. Any price data from before October 2025 is useless for these contracts.
A worked example
Here is a Restricted to Classified contract mixing two collections. Rarities, collections and float ranges come from the game's item file.
- 7 × SSG 08 | Fever Dream (Restricted, Prisma 2 Collection, range 0 to 0.72), each at 0.10 float
- 3 × UMP-45 | Plastique (Restricted, CS20 Collection, range 0 to 0.80), each at 0.20 float
Odds. Prisma 2 has 7 of the 10 inputs and three Classified skins, so each gets 70% ÷ 3 = 23.3%. CS20 has 3 inputs and three Classified skins, so each gets 30% ÷ 3 = 10%.
Float. Fever Dream normalizes to 0.10 ÷ 0.72 = 0.139. Plastique normalizes to 0.20 ÷ 0.80 = 0.25. The average is (7 × 0.139 + 3 × 0.25) ÷ 10 = 0.172.
| Possible output | Range | Chance | Float |
|---|---|---|---|
| AK-47 | Phantom Disruptor | 0 to 0.65 | 23.3% | 0.112 (MW) |
| MAC-10 | Disco Tech | 0 to 1.00 | 23.3% | 0.172 (FT) |
| MAG-7 | Justice | 0 to 1.00 | 23.3% | 0.172 (FT) |
| AUG | Death by Puppy | 0 to 0.40 | 10% | 0.069 (FN) |
| MP9 | Hydra | 0 to 1.00 | 10% | 0.172 (FT) |
| P90 | Nostalgia | 0 to 0.57 | 10% | 0.098 (MW) |
Notice the split. The same contract gives Field-Tested outputs on full-range skins and Factory New on the AUG, because its range stops at 0.40. Under the old raw-average formula the average would have been 0.13, and the full-range outputs would have landed in Minimal Wear. That is the kind of difference that turns a profitable contract into a losing one, and why any calculator you use must apply the current formula.
To get the full-range outputs into Minimal Wear, the normalized average would need to drop below 0.15, which means cleaner inputs, not more of them.
What TradeUpLab does
Based on its own site, checked on October 4, 2026, TradeUpLab offers:
- A calculator. You add ten inputs (or five Coverts). It lists every possible output with its chance, predicts the output float using the normalized formula above, and estimates expected value and the chance the contract ends in profit. The site says it enforces the StatTrak rule and switches to the five-input rule when you add Coverts.
- Lists of contracts. A page of trade-ups its system flags as profitable, a separate "risky" list, and an item database with prices.
- Prices from the Steam Market. The site says it monitors Steam Market prices continuously.
- A paid tier. Premium costs $10 a month, with benefits delivered through Discord. It shows new contracts three hours before free users, plus premium-only contracts.
Two things to keep in mind. A published "profitable" contract is a snapshot: once many people see it, the input prices tend to rise. And a profit figure built on Steam Market prices tells you nothing about what you net after fees, because selling there costs 15% on top of what the seller receives (see our Steam Market fees guide). Check whether any calculator's number includes fees before you trust it.
Other calculators and doing it by hand
- TradeUpSpy is another trade-up calculator and contract finder.
- CS2Cap publishes its trade-up calculator as open-source code on GitHub (MIT license) and says it tracks prices across about 40 marketplaces.
- A spreadsheet. The three formulas on this page are all you need. Pull float ranges from a skin database, use the actual floats of the copies you can buy, and use the price you would really sell at after fees.
Whichever you use, check that it applies the post-October 2025 rules: equal odds per input and normalized floats. A tool that still averages raw floats will mislabel the wear on many contracts.
Mistakes that cost money
- Trusting expected value alone. A contract can be profitable on average and still lose on most runs if the value sits in one unlikely output. Look at the chance of profit, not just the average.
- Using listing floats you cannot buy. Plug in the floats of the exact copies you will purchase.
- Ignoring fees and holds. Selling on the Steam Market costs 15% on top of what you receive, and traded items are held before they can be traded again.
- Using stale prices. Prices of popular inputs move once a contract becomes known.
Trade-ups are a random draw with real money attached. Only use skins you can afford to lose. For where to buy and sell inputs, see our skin trading sites guide.