How to Trade Up to UMP-45 | Grand Prix
UMP-45 | Grand Prix drops from Chroma 2 Case, so any contract that can produce it needs 10 Mil-Spec skins from that same case. Here is what the contract costs, what else it can land on, and the input float you need for each exterior.
- Odds per contract
- 25% 1 in 4
- Contract cost from
- $2.50 10 × cheapest input
- Expected value
- $1.54 mean of the outcome pool
- Margin
- -38.4% $-0.96 per contract
Buying is cheaper than rolling. A Field-Tested UMP-45 | Grand Prix costs $1.32 outright, against $2.50 for a contract with a 25% chance of producing one. Trade up for the process, not the value.
The contract
10 inputs, all Mil-Spec, all from Chroma 2 Case. Concentrating every input in one case is what keeps your odds at 25% — mixing cases splits the probability across both pools and lowers your chance at UMP-45 | Grand Prix specifically.
Negev | Man-o'-war
P250 | Valence
Negev | Man-o'-war
MP7 | Armor Core
Desert Eagle | Bronze Deco
Sawed-Off | Origami
Desert Eagle | Bronze Deco
Sawed-Off | Origami
P250 | Valence
P250 | Valence
MP7 | Armor Core
Sawed-Off | Origami12 further eligible inputs are available — open the reverse trade-up finder to price a full contract against your own inventory.
What else this contract can land on
A contract from Chroma 2 Case draws uniformly from every Restricted SMG skin in the pool, so UMP-45 | Grand Prix is one of 4 equally likely results. These are the other 3.
| Outcome | Odds | Cheapest price |
|---|---|---|
| AWP | Worm God | 25% | $2.19 |
| CZ75-Auto | Pole Position | 25% | $1.36 |
| UMP-45 | Grand Prixyour target | 25% | $1.32 |
| MAG-7 | Heat | 25% | $1.28 |
Input float for each exterior
CS2 normalises float across a trade-up: each input’s float becomes a 0–1 position inside its own range, those are averaged, and the average is applied to UMP-45 | Grand Prix’s range of 0.25–0.35. To land a given exterior, your ten inputs must average the normalised float below.
| Target exterior | Output float | Required avg. input float |
|---|---|---|
| Factory New | — | not reachable |
| Minimal Wear | — | not reachable |
| Field-Tested | 0.3000 | 0.5000 |
| Well-Worn | — | not reachable |
| Battle-Scarred | — | not reachable |
“Not reachable” means UMP-45 | Grand Prix’s own float range never enters that exterior band — no combination of inputs can produce it.
Build this contract
Price a full ten-slot contract against live inputs, set your own float values, and see the outcome odds update as you go.