Start with the return, not the big number
Decimal odds show your total return for every rand staked, including the stake itself. At 2.50, a winning R50 bet returns R125, not R125 plus your R50.
Your profit would be R75. If the bet loses, you lose the R50 stake.
The prices below are worked examples, not current bookmaker offers. They explain the maths, not which bets to place.
Decimal odds in rands
Multiply your stake by the decimal odds to calculate the total return. Subtract the stake to find the profit.
| Odds | Return | Profit |
|---|---|---|
| 1.50 | R75 | R25 |
| 2.00 | R100 | R50 |
| 2.50 | R125 | R75 |
| 4.00 | R200 | R150 |
Shorter odds mean a smaller potential profit for the same stake. They don't make a selection safe.
Fractional and American odds
Fractional odds describe profit relative to stake. At 3/2, a winning R50 stake makes R75 profit, with R125 returned altogether.
Divide the first number by the second, then add one to convert fractional odds to decimals. So 3/2 becomes 2.50.
Positive American odds show the profit on a stake of 100 units. At +150, that profit is 150 units, equivalent to decimal odds of 2.50.
Negative American odds show the stake needed to make 100 units of profit. At -200, staking 200 units makes 100 units of profit if it wins, equivalent to 1.50.
The probability implied by the price
Divide 100 by the decimal odds to get the implied probability as a percentage. Odds of 2.50 imply 40%; odds of 2.00 imply 50%.
That is the probability implied by the price, not proof of the outcome's actual chance. Calling something a favourite doesn't settle the match.
Why the percentages can exceed 100%
Take a three-way market priced at 2.00, 3.50 and 4.00. Those prices imply 50%, about 28.57% and 25%, adding up to about 103.57%.
The excess over 100% is the overround. It shows why a bookmaker's prices aren't a clean, margin-free forecast.
Compare the same bet
A higher price is only a useful comparison when the selection and settlement rules match. A football match-winner market and a team-to-qualify market are not the same bet.
- Check the event, selection and market name.
- Check whether extra time counts.
- Check whether the price has changed before confirming.
- Check the stake and total return on the final bet slip.
Accumulators multiply the odds, and the conditions
For a simple two-leg accumulator, multiply the decimal odds together. Two selections at 2.00 and 1.50 combine to 3.00, so a winning R50 stake returns R150.
Both selections must win for that straightforward example to pay out. Void bets and other settlement situations depend on the market and bookmaker rules.
Use the accumulator calculator to check the arithmetic. A larger potential return is not a reason to add another selection.
The number to remember
Return includes your stake; profit does not. Check that distinction before deciding whether a price is worth considering.