Break-even calculator
Enter a price to see the win rate you need just to break even. It is why a standard -110 line asks for 52.4 percent, not 50.
Result
Break-even win rate
52.38%
Decimal odds
1.9091
Break-even is the price's implied probability
The break-even win rate is simply the implied probability of the price you are paying. Anything above it is profit over the long run; anything below it loses. Laying -110 is a losing game unless you win more than 52.4 percent, which is exactly the margin the book is charging. Knowing your break-even number turns a hunch into a threshold you can measure against.