Decimal, Fractional and Moneyline Odds
Understanding Decimal Odds
Decimal odds are the standard format at most Australian bookmakers. The number represents your total return per dollar staked, including your original stake. Decimal 2.50 on a $10 bet returns $25 total ($15 profit plus $10 stake).
To calculate implied probability from decimal odds, divide 1 by the decimal and multiply by 100. Odds of 2.00 imply a 50% chance — but this is the bookmaker's assessment, not a guarantee of outcome.
Fractional Odds Explained
Fractional odds (e.g. 5/1 or 3/2) show profit relative to stake. 5/1 means $5 profit for every $1 staked. Fractions are common on UK-facing platforms and racing forms, and many Australian bettors encounter them on international events.
Converting 5/1 to decimal: divide numerator by denominator, add 1 → 6.00. A $10 stake at 5/1 returns $60 total if successful.
| Decimal | Fractional | Moneyline | Implied % |
|---|---|---|---|
| 1.50 | 1/2 | -200 | 66.7% |
| 2.00 | 1/1 | +100 | 50.0% |
| 3.00 | 2/1 | +200 | 33.3% |
| 5.00 | 4/1 | +400 | 20.0% |
American Moneyline Format
Moneyline odds use positive numbers for underdogs (+250) and negative numbers for favourites (-150). Positive odds show profit on a $100 stake; negative odds show how much you must stake to profit $100.
Australian operators rarely display moneyline by default, but you may see them on US sports markets. Understanding all three formats helps when comparing prices across platforms or reading international analysis.
Comparing Prices Across Formats
When shopping for the best price, convert all formats to decimal for direct comparison. A small difference in odds compounds over time, but chasing marginal gains should never lead to staking beyond your budget.
Bookmakers build a margin (overround) into their prices, meaning implied probabilities across all outcomes exceed 100%. This edge ensures operator profitability regardless of individual results.
Practical Tips for Australian Bettors
Most licensed AU bookmakers let you switch display formats in settings. Choose whichever you find most intuitive. Focus on understanding what return you stand to receive relative to your stake, and never wager more than you can afford to lose.