How to Read Fractional Odds

How to read 7/1, 5/4 and evens

Fractional odds are written as two numbers separated by a slash, and the whole format rests on one simple idea: the number on the left-hand side of the fraction represents the potential profit if you stake the number on the right-hand side¹.

So when you see 7/1, read it as "seven to one": you win 7 units of profit for every 1 unit you put down. A few common examples make the pattern clear¹:

• 10/1: £10 profit for every £1 staked
• 5/2: £5 profit for every £2 staked
• 4/11: £4 profit for every £11 staked

Notice that last one. The profit is smaller than the stake. When the number on the left-hand side is smaller than the number on the right-hand side, the bet is referred to as odds-on, which tells you the outcome is considered strongly likely¹. You can read more about what odds-on prices mean for favorites and longshots in odds-on, evens and odds-against.

At the other end of the scale sits the simplest fraction of all: odds of 1/1 are referred to as evens¹. Evens means you win exactly the amount you staked. Bet 10, win 10, and get your 10 back.

One thing to keep straight: fractional odds quote your profit, not your total return. Your stake comes back on top when you win. If you want a fuller breakdown of how stake, profit and return differ across odds formats, see stake, profit and return.

Payout examples: £1 at 2/1 and £10 at 5/1

The easiest way to internalize fractional odds is to run a few real payouts.

£1 at 2/1. A £1 bet on a team to win at 2/1 will return £3 if successful¹. That breaks down as £2 of profit plus your original £1 stake. The same bet written in decimal odds, 3.00, returns the same £3: £2 profit plus the £1 stake¹. The two formats describe the identical payout.

£10 at 5/1. Here the fraction says you win 5 for every 1 staked, so a £10 stake earns £50 in profit. Add the returned stake and the total payout is £60.

A horse at 1-5. Racing examples work the same way even when the currency changes. A horse at odds of 1 to 5 pays $5.00 per $1.00 bet, so a minimum $2.00 bet pays $10 (5 x 1 x $2) plus your $2 stake, for a total of $12 CAD⁴. This is an odds-on price: the favorite pays less than double your money because it is expected to win.

A coin flip at 10/11. A fair coin flip is a 50/50 proposition, but a gambling company offering a bet on a coin flip would likely offer 10/11 for both heads and tails⁵. At 10/11 you win 10 units for every 11 staked, slightly less than even money. That gap is the operator's margin, the same commission built into every two-way price; we cover it in vig or juice explained.

Casino side bets quoted "to 1". Fractional-style payouts also appear on casino floors. In Macau, a sevens side bet pays 150 to 1 for two sevens of the same suit and 5000 to 1 for three sevens of the same suit³. The "to 1" phrasing works exactly like a fraction: 150 to 1 means 150 units of profit per 1 unit staked. There is a subtle difference between "to one" and "for one" quoting that trips up new players, which we explain in "to one" vs "for one".

Craps true odds. The odds bets in craps are quoted as fractions because they pay at true odds with no house edge: the true odds are 1/3 (about 33.33%) on 4 or 10, 2/5 (about 40%) on 5 or 9, and 5/11 (about 45.46%) on 6 or 8⁶.

Fractional vs decimal and American odds

Fractional odds are one of three major formats you will meet. The same price can be written all three ways, and a single football match shows how they line up. For an England v Spain match, one operator quotes England win at 2/1 (fractional), 3.00 (decimal) or +200 (American odds); Spain win at 5/4 (fractional), 2.25 (decimal) or +125 (American); and the draw at 3/1 (fractional), 4.00 (decimal) or +300 (American)¹.

The differences between the formats are about what they show:

• Fractional odds show profit relative to stake. They are the traditional British format.
• Decimal odds show your total return per unit staked, stake included. The equivalent of 1/1 odds in decimal is 2.00¹. Lower decimals mean the outcome is deemed more likely, while higher numbers mean it is deemed less likely and will return more².
• American odds show how much a 100-unit stake wins (with a plus sign) or how much you must stake to win 100 (with a minus sign). We break that format down in American odds explained.

Converting fractional to decimal. Take the numerator (the number on the left) and divide it by the denominator (the number on the right), then add 1.00. For example, 7/4 equals 2.25 in decimal odds². Another worked example: 10/1 becomes 10 ÷ 1 = 10, and 10 + 1 = 11.00¹. The added 1 is your stake coming back.

Converting decimal to fractional. Subtract 1 from the decimal, express the result as a fraction and simplify. Starting with decimal odds of 2.50, subtract 1 to get 1.50, which as a fraction is 150/100, which simplifies to 3/2¹. Another example: 1.80 minus 1 is 0.80, which is 80/100, and 80/100 divided by 20 gives 4/5¹.

Which format you will meet where. You are most likely to see decimal odds in European betting markets, as British bettors typically use fractional odds, while American sites usually use moneyline odds². In Asia, nearly every operator quotes prices as decimal multipliers, so if you are used to fractions you will want the conversion above. Our page on which odds formats are used in each Asian jurisdiction maps this out country by country.

One practical difference worth knowing: decimal odds allow smaller increments than fractional odds. Where fractional 1/2 gives a 1.5x return, decimal odds can be fine-tuned to more specific values like 1.51 or 1.54². That is one reason the decimal format has spread so widely. For a fuller treatment of the decimal system, see decimal odds explained.

From odds to percentage probability

Every price implies a probability, and fractional odds make the arithmetic refreshingly direct: divide the right-hand number by the sum of both numbers. So odds of 9/1 give an implied probability of 10%¹.

Worked through:

• 9/1: 1 ÷ (9 + 1) = 10% implied probability¹
• Evens (1/1): 1 ÷ (1 + 1) = 50%, which is exactly what you would expect from a coin flip
• 4/11: 11 ÷ (4 + 11) = about 73%, a strong favorite

The implied probability is simply what the odds say about a selection's chances: divide the right-hand number by the sum of both numbers, so odds of 9/1 give an implied probability of 10%⁵. If you want to go further and strip the operator's margin out to see the true underlying chances, see fair odds: how to remove the margin.

Reading odds as probabilities is also how you judge whether a price is generous. A craps example shows the idea in reverse: the chance of rolling a 5 before a 7 with two dice is 40% (6/4), and the odds bets pay fractions that match those chances exactly, which is why they carry no house edge⁶.

Where you will still see fractional odds

Even in Asia, where decimal multipliers dominate, fractional-style prices still surface in several places.

British and Irish bookmakers. The format's home turf. If you bet with a UK-facing operator, or read British racing coverage, prices will be quoted as fractions like 5/2 or 7/2².

Casino table payouts. Side bets and proposition bets are routinely quoted "to 1", as with the Macau sevens bet paying 150 to 1 and 5000 to 1³. These are fractional odds in plain clothing.

Fixed-odds rules at racing operators. The Hong Kong Jockey Club's fixed-odds rules describe payouts in terms of the stake being multiplied by the fixed odds if the selection wins, and note that the operator may change the fixed odds of a bet type at any time⁷. Fixed-odds pricing of this kind, where your price is locked when you bet, is the natural home of fractional quotes; contrast this with pari-mutuel pools, where your dividend depends on how much everyone else bet, covered in how pari-mutuel dividends are calculated.

Asian racing, but in decimal dress. Japan's horse racing shows odds as an approximate multiplier of the payout if the ticket you bought wins, and lower odds mean the horse is favored by many people, so your return is lower⁸. Kasamatsu Keiba defines odds the same way: an approximate multiplier showing the payout if the ticket bought wins⁹. Boat race odds work similarly; if you predict the finishing order 1-3, the odds (payout) would be 8.4 times the amount of your bet¹⁰. These are all decimal multipliers, but the underlying idea, a ratio between stake and payout, is the same one fractional odds express.

Singapore fixed-odds football. Singapore Pools quotes fixed prices in decimal form and multiplies them through your bet; for example, a 1/2 Goal Trebles stake of S$30 at odds of 1.50, 1.67 and 1.20 pays S$30 x 1.50 x 1.67 x 1.20 = S$90.18¹¹. If you are used to fractions, the conversion rule from earlier turns any of these into a fractional equivalent.

If you are comparing prices across operators in different formats, the overview of every odds format used in Asia puts fractional odds in context alongside decimal, American, Malay, Indonesian and Hong Kong odds.

A quick reference

To get the implied probability from any fractional price, divide the right-hand number by the sum of both numbers: for 9/1, that is 1 divided by 10, which is 10%⁵.

The conversions follow the rules from earlier sections: divide the left number by the right and add 1 for decimal², divide the right number by the sum of both for implied probability¹, and the England, Spain and draw examples show the fractional, decimal and American columns lining up¹. Keep this table handy and any fraction you meet, from a British racing price to a craps odds bet, becomes a payout you can work out in your head.