18+ Gamble responsibly. Free, confidential help 24/7:Free help 24/7: 1800 858 858We earn commission from partner links
Partner casinos

Free calculator

Odds converter: decimal, fractional, American and probability

Convert any price between decimal, fractional and American odds, see the implied chance, and check what a $10 bet returns.

Three interlocking gears with two-way arrows beside a calculator, illustrating an odds converter between formats

Odds converter

$10 bet returns
-
Profit on $10
-

Type in any box and the others update. Australian bookmakers and the TAB quote decimal odds, which include your stake.

Key facts

  • Australian bookmakers and the TAB quote decimal odds, which include your stake: $3.50 returns $3.50 for every $1.
  • Decimal to implied probability: 100 / decimal odds. $3.50 is a 28.6% chance.
  • Fractional 5/2 is the same price as decimal 3.50 and American +250.
  • Add up the implied chances of every outcome in a market: anything over 100% is the bookmaker's margin.

How to use the odds converter

Type a price into any of the four boxes and the other three update. The return and profit show what a $10 bet pays at that price, including your stake.

The three odds formats explained

Decimal odds show the total return for each $1 bet, stake included. They are the standard in Australia, used by every licensed bookmaker and the TAB. A $4.00 winner returns $4 for every $1: $3 profit plus your $1 back.

Fractional odds show profit relative to the stake. 3/1 means $3 profit for every $1, the same as decimal 4.00. They are still common in UK and Irish racing.

American odds are built around $100. A plus number is the profit on a $100 bet (+300 wins $300); a minus number is what you must bet to win $100 (-150 means bet $150 to win $100).

Conversion table for common prices

DecimalFractionalAmericanImplied chance
1.251/4-40080.0%
1.501/2-20066.7%
1.804/5-12555.6%
2.001/1 (evens)+10050.0%
2.503/2+15040.0%
3.002/1+20033.3%
4.003/1+30025.0%
6.005/1+50016.7%
11.0010/1+10009.1%
21.0020/1+20004.8%

Implied probability and the bookmaker's margin

Implied probability is the chance a price suggests, and it is 100 divided by the decimal odds. If you add up the implied chances of every runner or team in a market, the total is more than 100%. The extra is the bookmaker's margin.

Take a head to head game at $1.90 and $1.90. Each price implies 52.6%, so the market adds up to 105.3%. The 5.3% over the top is how the bookmaker gets paid whichever side wins. When you compare prices, the market with the smaller total gives you better value. Our value betting guide and the expected value calculator take that comparison further.

Pundit tip: a price only has value if you think the real chance is higher than the implied chance. Converting odds to percentages makes that comparison quick.

Odds in multis and exotics

Odds multiply in a multi: two legs at $1.90 and $2.10 combine to $3.99. Use the multi bet calculator to check a full slip, or the system bet calculator for a trixie, yankee or lucky 15. On an exchange the same decimal prices are used to lay, and the lay bet calculator turns a lay price into a liability. Exotic bets such as trifectas are paid by tote dividends rather than fixed odds; the boxed trifecta calculator shows what a box costs and your flexi percentage.

Frequently asked questions

How do I convert fractional odds to decimal?

Divide the first number by the second and add 1. 5/2 is 2.5 plus 1, so 3.50. 1/2 is 0.5 plus 1, so 1.50.

How do I convert American odds to decimal?

For a plus price, divide by 100 and add 1: +250 is 3.50. For a minus price, divide 100 by the number without the minus sign and add 1: -200 is 1.50.

What does $1.67 mean in betting?

Decimal odds of $1.67 return $1.67 for every $1 you bet, so a $10 bet returns $16.70, of which $6.70 is profit. The implied chance is about 60%, and it is the same price as fractional 2/3 or American -150.

What is implied probability?

It is the chance of an outcome that a price suggests, worked out as 100 divided by the decimal odds. Bookmakers build a margin into their prices, so the implied chances in a market add up to more than 100%.

Are decimal odds the same as tote dividends?

They are written the same way, as a return per $1 including the stake, but a tote dividend is only known after the race because it depends on the pool. Fixed odds are locked in when you bet. Read our guide to tote vs fixed odds.

Related reading