Methodology

Prices come from recent sales

Prices are aggregated from several marketplace APIs, such as Skinport, the Steam Community Market and other price APIs, in US dollars. For each item variant we take the median sale price over the last 7 days, or over 30 or 90 days when the shorter window has too few sales, and a variant gets a price only with a minimum volume of sales.

Knives and gloves rarely sell often enough on any one marketplace, so a variant one source cannot price takes its price from another.

A price that jumps far from the last accepted one waits for the next run to confirm it. If a source stops answering, prices fall back to another source until it is back.

Every table and price block is labelled as aggregated market prices and shows the time of its snapshot.

EV per open follows Valve's odds

Valve publishes the odds of each rarity tier: 79.92% Mil-Spec, 15.98% Restricted, 3.20% Classified, 0.64% Covert and 0.26% for the rare special item, a knife or gloves. Within a tier, every item is equally likely.

An item's value is the average over its variants. Wear is weighted by community estimates of how often each wear drops, within the float range the skin can roll. StatTrak is a 10% chance where the item can have it, and Doppler-style phases are equally likely.

EV per open is the sum over the tiers of each tier's odds times the average value of its items.

ROI and profit chance compare EV with the cost of one open

One open costs the case's market price plus its key, which Valve sells at a fixed price in its store.

ROI is EV divided by that cost. Profit chance is the exact probability that the item from one open is worth more than the cost of opening it.

A case with thin price data shows no EV

For every tier we measure the share of its drop probability whose variants have a recent price. If any tier falls short, the case shows "not enough price data" instead of a guess. Otherwise each tier averages over its priced variants only.

EV can also be switched off for a case while its prices are reviewed.

Figures are gross and computed once in US dollars

EV and ROI are gross: marketplace fees are not taken off.

Every figure is computed once in US dollars. The Turkish, Polish and Brazilian pages convert it with the day's European Central Bank reference rate, so the ranking order is the same in every language.

The simulator rolls on our server

Every simulated open is rolled on our server from a secret seed and the roll's own id, in a fixed order: tier, item, StatTrak, wear, float, pattern and phase. The same roll always gives the same item.

Simulated items have no cash value and never leave the simulator.