What is xG?
Expected goals, xG for short, is the chance that a shot becomes a goal, written as a number from 0 to 1. A shot worth 0.10 xG is one that is scored about once in every ten tries.
One number for one chance
Every shot gets a value between 0 and 1. The value comes from history: thousands of past shots taken from a similar place, in a similar way, and how many of them went in. If shots like this one were scored 10% of the time, this shot is worth 0.10 xG. If they were scored 79% of the time, as penalties are in Opta's model, it is worth 0.79.
xG is decided before the ball is struck. It does not care whether the shot then flew into the top corner or over the bar. It measures the chance, not the finish.
Adding chances up
A team's xG in a match is the sum of the xG of all its shots. Twelve shots worth 2.4 xG in total means the chances were good enough for about two goals on an ordinary day. The team may score none, or four: football is low-scoring, and a few shots decide a lot.
Two totals can hide very different matches. One chance of 0.60 and six chances of 0.10 both add up to 0.60 xG, but the single big chance gives a 60% chance of scoring at least once, the six small ones about 47%.
What xG is good for
- Reading a match beyond the score. A 1-0 win with 0.4 xG against 2.1 is a different story from a 1-0 win with 2.1 against 0.4.
- Judging a run of matches. Over a season, xG for and against says more about a team's strength than goals alone; analysts have shown it predicts future results better than past goals do.
- Following a live match. On Xgoals, live xG shows which side is creating the chances while the score stands still.
What xG is not
- Not the deserved score. It measures how good the chances were, nothing more.
- Not a promise. A team with more xG than goals is not "owed" anything; the next shot does not know about the last one.
- Not one official number. Each data company runs its own model, so the same shot can have different values on different sites. See why providers disagree.
Questions
What does 1.5 xG mean?
The chances a team created were good enough for about one or two goals on an ordinary day. It is an average over many similar chances, not a forecast for this match.
Is a high xG the same as a good performance?
Not on its own. xG measures chance quality. A team can create a lot and defend badly, or protect a lead and shoot little. Read it with xG against.
Who invented xG?
The idea of judging shots by how often similar shots are scored goes back to academic work in the 1990s; Opta introduced its xG in 2012, and TV brought it to a wide audience from 2017.
Sources
- Opta Analyst: What is expected goals (xG)? · 2023
- Hudl StatsBomb: Expected goals (xG) explained
- Bajons & Kook: expected goals models (arXiv) · 2025
- American Soccer Analysis: is xG the best predictor of future results? · July 2022
- Xgoals: How we measure · 2026
Checked 2026-10-28. Methods change: every figure here is dated to its source.
xG explains football; it is not a betting tip. 18+ · Please gamble responsibly.