Betting Odds Calculator: Convert Odds and Work Out Your Returns
Use the free calculator below to work out exactly what a bet will return, convert between decimal, fractional and American odds, price up an each-way bet or a multi, and see how much margin a bookmaker has built into a market. Underneath, we explain how odds work in plain English, with worked examples and a full conversion table.
Last updated: 6 October 2026.
Decimal odds include your stake. Fractional and American odds show profit only, so the calculator converts them for you.
An each-way bet is two bets of equal size: one to win and one to place. Many Australian bookmakers set their own fixed place price, so choose "Enter place odds" to use it.
Multi odds are the legs multiplied together. Every leg must win. Same Game Multi prices can differ because bookmakers adjust for linked outcomes.
Enter every outcome in one market (for example both teams in a head-to-head). The further the market percentage is above 100%, the bigger the bookmaker's built-in margin.
How to use it: pick a tab, type in your odds and stake, and the results update instantly. All results are calculations only. They show what a bet would pay, not whether it is likely to win.
How Betting Odds Work
Odds tell you two things at once: how much a bet pays and how likely the bookmaker thinks the outcome is. Australia uses decimal odds almost everywhere, which makes the maths simple. You will still see fractional odds in UK racing coverage and American odds on US sports sites, which is why the converter above handles all three.
| Format | Looks like | What the number means | Where you will see it |
|---|---|---|---|
| Decimal | 2.50 | Total return for every $1 staked, including your stake | Australian and European bookmakers |
| Fractional | 3/2 or 6/4 | Profit relative to stake (win $3 for every $2 bet) | UK and Irish racing, older form guides |
| American (moneyline) | +150 or -200 | Positive: profit on a $100 bet. Negative: stake needed to win $100 | US sports betting sites and broadcasts |
Decimal Odds: The Australian Standard
To find your total return, multiply your stake by the decimal odds. Your profit is the return minus your stake.
Example: $20 on a team at $2.50 returns $20 x 2.50 = $50. Your profit is $30.
The lowest possible decimal price is just above $1.00. A price of $1.10 is a heavy favourite (a $100 bet makes just $10 profit), while $51.00 is a big outsider.
Fractional Odds
Fractional odds show profit compared to stake. At 5/2, you win $5 profit for every $2 you bet. To convert to decimal, divide the top number by the bottom number and add 1: 5 / 2 + 1 = 3.50. “Evens” (1/1) is the same as $2.00.
American Odds
American odds use 100 as the reference point. A positive number (+250) is the profit on a $100 bet, so decimal = 1 + 250 / 100 = 3.50. A negative number (-150) is how much you must bet to make $100 profit, so decimal = 1 + 100 / 150 = 1.67.
Odds Conversion Table
The most common prices in all three formats, with the implied chance of each.
| Decimal | Fractional | American | Implied chance | Return on $10 |
|---|---|---|---|---|
| 1.50 | 1/2 | -200 | 66.7% | $15.00 |
| 1.80 | 4/5 | -125 | 55.6% | $18.00 |
| 1.91 | 10/11 | -110 | 52.4% | $19.10 |
| 2.00 | 1/1 (Evens) | +100 | 50.0% | $20.00 |
| 2.50 | 6/4 (3/2) | +150 | 40.0% | $25.00 |
| 3.00 | 2/1 | +200 | 33.3% | $30.00 |
| 4.00 | 3/1 | +300 | 25.0% | $40.00 |
| 5.00 | 4/1 | +400 | 20.0% | $50.00 |
| 6.00 | 5/1 | +500 | 16.7% | $60.00 |
| 11.00 | 10/1 | +1000 | 9.1% | $110.00 |
| 21.00 | 20/1 | +2000 | 4.8% | $210.00 |
| 51.00 | 50/1 | +5000 | 2.0% | $510.00 |
| 101.00 | 100/1 | +10000 | 1.0% | $1,010.00 |
Implied Probability: What the Odds Say About Your Chances
Every price can be turned into a percentage chance. Divide 1 by the decimal odds and multiply by 100.
Example: 1 / 4.00 = 0.25, so a $4.00 price implies a 25% chance. In other words, the bookmaker thinks this outcome happens about one time in four.
Implied probability also tells you your break-even strike rate. If you always bet at $1.90, you need to win 1 / 1.90 = 52.6% of your bets just to break even.
| If you bet at | You need to win | Roughly |
|---|---|---|
| $1.50 | 66.7% of bets | 2 in 3 |
| $1.90 | 52.6% of bets | Just over 1 in 2 |
| $2.50 | 40.0% of bets | 2 in 5 |
| $4.00 | 25.0% of bets | 1 in 4 |
| $10.00 | 10.0% of bets | 1 in 10 |
Bookmaker Margin (Overround) Explained
If a market was perfectly fair, the implied chances of every outcome would add up to exactly 100%. In practice they add up to more, and the extra is the bookmaker’s margin, also called the overround.
Worked example: a head-to-head market has Team A at $1.80 and Team B at $2.05.
- Team A: 1 / 1.80 = 55.6%
- Team B: 1 / 2.05 = 48.8%
- Market total: 104.3%, an overround of 4.3%
Removing the margin gives the “fair” odds: Team A about $1.88 and Team B about $2.14. The gap between the fair odds and the odds on offer is how the bookmaker makes money over time. Use the Bookmaker margin tab in the calculator to test any market.
| Market type | Typical market percentage | What it means for you |
|---|---|---|
| Head-to-head on major sports | Around 103% to 106% | Smaller margin, better value |
| Line and totals | Around 104% to 106% | Prices close to $1.90 each side |
| Player props | Often 110% or more | Higher margin, so shop around |
| Big-field racing (e.g. Melbourne Cup) | Often 115% or more, especially early | Large margins spread across many runners |
Typical ranges vary between bookmakers and events. Use the calculator to check a real market.
Each-Way Bets: How Returns Are Calculated
An each-way bet is two bets: one to win and one to place. A “$10 each way” costs $20. Place odds are either a fraction of the win odds (common in the UK) or a separate fixed place price set by the bookmaker (common in Australia).
Example with 1/4 place terms: $10 each way at $11.00. Place odds = 1 + (11 – 1) / 4 = 3.50.
| Result | Win part | Place part | Total return | Profit |
|---|---|---|---|---|
| Wins | $110.00 | $35.00 | $145.00 | +$125.00 |
| Places but does not win | $0 | $35.00 | $35.00 | +$15.00 |
| Unplaced | $0 | $0 | $0 | -$20.00 |
Multi Bets: Multiplying the Odds
A multi links two or more selections. The odds are multiplied together, and every leg must win for you to get paid.
Example: three legs at $1.80, $2.10 and $1.50. Combined odds = 1.80 x 2.10 x 1.50 = $5.67. A $10 multi returns $56.70.
The catch is the implied chance: 1 / 5.67 = 17.6%. Each leg looks likely on its own, but together they win less than one time in five. Bookmaker margins also multiply with every leg you add.
Expected Value: Is the Price Worth It?
Experienced punters compare the odds on offer with their own estimate of the chance. If your estimate is higher than the implied chance, the bet has positive expected value on paper.
Example: you believe a team wins 60% of the time and the price is $1.80 (implied 55.6%). Expected value per $1 = 0.60 x 1.80 – 1 = +$0.08. In theory, 100 bets of $10 at those numbers would average an $80 profit.
Be careful: this only works if your 60% estimate is genuinely accurate, and most people overestimate their edge. Because of the bookmaker margin, the majority of punters lose money over time.
Remember: a calculator can tell you what a bet pays, but it cannot tell you what will happen. Treat betting as paid entertainment and set a budget you are comfortable losing.
Dead Heats, Deductions and Other Adjustments
| Situation | How it is usually settled | Example |
|---|---|---|
| Dead heat (two-way tie for a place that pays) | Your stake is divided by the number of tied runners, then paid at full odds | $10 at $5.00, two-way dead heat for 1st: $5 x 5.00 = $25 return |
| Late scratching (racing, fixed odds) | A deduction in cents in the dollar is taken from winnings | $10 at $8.00 with a 15c deduction: $70 x 0.85 = $59.50 winnings, $69.50 return |
| Void or abandoned event | Stake refunded; in a multi that leg is usually treated as $1.00 | A 3-leg multi with one void leg is settled as a 2-leg multi |
| Tote betting | No deductions; the dividend is set by the pool after the event | Dividend known only once results are official |
Each bookmaker publishes its own rules. Always check the terms that apply to your bet.
Betting Responsibly in Australia
- Only use bookmakers licensed by an Australian state or territory. You can check a provider on ACMA’s register of licensed wagering providers.
- Credit cards cannot be used with licensed online wagering providers (since 11 June 2024).
- Set deposit limits and review your activity statements regularly.
- BetStop, the National Self-Exclusion Register, lets you block yourself from all licensed online and phone wagering providers.
- Free, confidential support is available 24/7 from Gambling Help Online on 1800 858 858.
Read more on our responsible gambling page.
Betting Odds FAQs
How do I calculate betting returns?
Multiply your stake by the decimal odds. A $10 bet at $3.20 returns $32, which includes your $10 stake, so your profit is $22.
What does $2.50 mean in betting?
$2.50 means you get back $2.50 for every $1 you bet, including your stake. A $10 bet returns $25 (a $15 profit). The implied chance is 40%.
What odds format is used in Australia?
Australian bookmakers use decimal odds. Fractional odds are mostly seen in UK racing, and American odds on US sports sites.
What does evens mean?
Evens means you win the same amount as you bet. It is 1/1 in fractional odds, $2.00 in decimal odds and +100 in American odds.
How do I convert fractional odds to decimal?
Divide the first number by the second and add 1. For example, 7/2 is 7 / 2 + 1 = 4.50.
What is implied probability?
It is the chance of an outcome according to the odds. Divide 1 by the decimal odds: $5.00 implies a 20% chance.
What is overround?
Overround is the amount by which a market’s implied probabilities add up to more than 100%. It represents the bookmaker’s built-in margin.
Does a good calculation mean a bet will win?
No. The calculator only shows what a bet pays and what the odds imply. It cannot predict results, and no betting system guarantees a profit.
Related Guides
Put the calculator to work with our Melbourne Cup betting guide and AFL betting markets guide, or read our football betting guide and betting rules.
Sources: Australian Communications and Media Authority (acma.gov.au), BetStop (betstop.gov.au), Gambling Help Online (gamblinghelponline.org.au). Gambling involves risk. Only bet what you can afford to lose. 18+ only.
