Odds calculator
Put in the price and the stake and this tells you what the bet pays back and what chance the price gives it. It does the arithmetic the book has already done before it hung the number.
- Winnings
- $90.91
- Total payout
- $190.91
- Implied probability
- 52.4%
- American odds
- -110
- Decimal odds
- 1.91
- Fractional odds
- 10/11
What it tells you
Type a price in any format and a stake, and you get the profit, the total that comes back to you, and the implied probability. At -110, $110 wins $100 and $210 comes back, and the price says the bet wins 52.38 percent of the time. That last figure is the one I'd look at first. It is the line you have to beat, every time, before the bet has earned you a cent.
The mistake people make
They read the implied probability as the book's opinion of the game. It isn't, quite, and the difference is the whole business of booking: the book sets each price a little short of fair on both sides, so that whatever happens on the field, the money it takes in covers what it pays out with something left over. Both sides of a game add up to more than 100 percent, because the book's cut is built into the prices (the vigorish page shows how). So 52.38 percent is what you need to win to break even at that price, not what the book thinks will happen. I'd keep the two ideas apart: one is your break-even, the other is the book's view with its margin removed. If you want the second, use the no-vig calculator. The implied probability guide goes through the method by hand, which I think everyone should do once.