Soccer Expected Goals (xG) Calculator

Expected goals (xG) models used by professional analytics departments are built from historical databases of hundreds of thousands of shots, weighing angle, distance, defensive pressure, and body part. This calculator is a simplified stand-in that instead applies flat conversion rates by shot category: about 12% for a shot inside the box, 3% outside the box, 76% for a penalty kick, and 6% for a header — figures chosen to roughly track typical professional conversion rates for each category, not derived from a live statistical model. Because headers and box location can overlap (a header taken from inside the box is still a header), the engine subtracts an estimated overlap before applying box-location rates to the remaining non-header, non-penalty shots, so it isn't simply summing all five input categories independently — it's trying to avoid double-counting the same shot under two different rates.

Total xG is the sum of those adjusted category values. xG per shot divides that total by shot volume, useful for comparing shot selection quality between two performances with very different shot counts. Shot accuracy is a separate, simpler stat — just shots on target over total shots — that measures accuracy, not quality of chance. The xG outperformance figure is the least standard output here: it's a heuristic derived from this calculator's own xG total scaled by shot accuracy and the share of shots taken from inside the box, meant to gesture at how much a clinical finisher might exceed their raw xG rather than a validated metric — treat it as a directional signal, not a number to cite alongside real xG data.