It depends on their exact formula. Roughly, though: Probabilty of Team A beating Team B, given that Team A has 'A' Elo points and Team B has 'B' Elo points: 10

It depends on their exact formula. Roughly, though: Probabilty of Team A beating Team B, given that Team A has 'A' Elo points and Team B has 'B' Elo points: 100/(1+10^((A-B)/400))