What are Fractional Odds?

Fractional odds are the most traditional format of listing odds and show bettors the probability of an event happening – and how much can be made from a bet on that event.

How to Calculate Winnings with Fractional Odds

As an example we will use the fractional odds for an English soccer game.

You may see on BettingTop10 that Liverpool is 1/2 to win the game, while Watford is 5/1.

If you were to stake $10 on Liverpool to win you would receive $5 + your original $10 stake if your prediction was correct. A $10 bet on Watford would pay out $50 + your original $10 stake.

As you can see, the simple formula here is with an underdog is the number to the left of the slash, multiplied by your stake, equals the winnings.

5/1 = 5 x $10 = $50 + $10 original stake

With a favourite your stake is divided by the number to the right of the slash.

1/2 = $10 divided by 2 = $5 + $10 original stake.

How to Convert Fractional Odds to Decimal Odds

Most betting sites will have an inbuilt fractional odds calculator but here is a simple way to convert the odds.

Just divide the fraction and add 1.

In the examples we used before the odds for a Liverpool win would be 1.5

1/2 = 1 divided by 2 = 0.5 + 1 = 1.5

The Watford decimal odds are 6.00

5/1 = 5 divided by 1 = 5 +1 = 6.00

Here is a handle conversion table covering some of the most popular betting odds.

1/2 = 1.50
1/1 = 2.00
2/1 = 3.00
3/1 = 4.00
4/1 = 5.00
5/1 = 6.00
10/1 = 11.00
25/1 = 26.00
50/1 = 51.00
100/1 = 101.00

How to Convert Fractional Odds to American Odds

In Canada you may be more used to seeing American odds – but these can be converted. For underdog fractional odds (over 1/1) first convert into decimal then multiply by 100.

5/1 = 5 divided by 1 = 5 +1 = 6 x 100 = +600

For favourites you will need to divide -100 by the fractional odds as a decimal.

1/2 = -100 divided by 1/2 (0.5) = -200

Here’s the conversion table.

½ = -200
1/1 = +100
2/1 = +300
3/1 = +400
4/1 = +500
5/1 = +600
10/1 = +1000
25/1 = +2500
50/1 = +5000
100/1 = +10000

How to Calculate Sports Odds

For different sports, it is simple when you have had fractional odds explained.

A soccer game will usually have home/draw/away prices. The example we used before can be used here again.

Liverpool

1/2

The Draw

3/1

Watford

5/1

The potential winnings are as before.

NBA wagers tend to concentrate on the points spread and totals and generally listed with American odds but they can be converted to fractional odds.

The Knicks would be +5.5 at 91/100 LA Clippers -5.5 at 91/100

You can see that a $10 on either of these would return $19.10

With a totals bet you place a wager on the number of points being over or under a set amount. Again, these will usually have the same odds.

For example, the over/under might be O 205.5         U 205.5  at  91/100

The winnings on a $10 wager would once again be $19.10

In the NFL a Moneyline bet is just like the soccer bet we looked at – but without the possibility of a tie.

So it could look like this:

Buffalo Bills

5/1

Minnesota Vikings

1/2

A $10 winning bet on the Bills here would get you $60 (5 x 10 + original stake of 10)

An over/under bet on an NFL game would work exactly like the NBA example.

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