De-vigging a three-way market

Same method as a two-way market, with three outcomes. Convert home, draw and away to probabilities, add all three, and divide each by the sum.

Soccer markets need this more than American ones because the third outcome carries real weight — a draw is not a rounding error, it is frequently the most likely single result in a low-scoring fixture.

Three-way markets usually carry a larger overround than two-way ones. That is a structural fact about how soccer is priced rather than a judgement about any particular operator.

That is also the expensive part. A reader arriving from American sport reads the two team prices as a complete market. They are not, and a team backed to win loses on a draw — which is roughly a quarter of all fixtures.

What to do with it. Always sum all three prices before comparing anything, and check whether the market you are looking at includes the draw or has had it removed.

Work it out. The no-vig calculator takes both sides of a market and returns the margin and the fair price of each.