Margin (Overround)

If you add the implied probabilities of all outcomes in a market (1 / odds for each outcome), the sum exceeds 100%. The excess is the operator's margin. A 1X2 football market with implied probabilities summing to 105% has a 5% margin. Lower margin = better odds for you. Top operators in Kenya run 5-8% margins on Premier League; lower leagues and obscure markets are typically 10-15%.