# Sports betting security: How betting odds are calculated The odds are the most important value at all betting agencies. Odds can vary. The higher the value, the less likely the odds are to succeed, according to the bookmaker.

### What are the odds for a bet?

The odds are a numerical multiplier that shows the possibility of a particular event in a sport and includes the bookmaker’s margin. The odds let the bettor know what the potential winnings (profit) of the bet are. The odds can change both due to changes in the probability of the event, and due to “line-loading”.

The bookmaker determines the probability of the outcome as a percentage and expresses the value in odds, which puts a margin in order to make a profit, regardless of the volume of betting on the different markets and the outcome of the event. Betting odds come in three formats:

• decimal;
• fractional;
• American.

### Decimal (European) odds

Decimal odds are common in Europe, insbesondere in Deutschland, CIS countries and some Asian countries. The decimal odds multiplied by the nfl live betting sum allows you to find out the amount of potential payout. For example, a Vulkanbet bookmaker betting \$100 at odds of 1.91 will have a potential payout of \$191 (100 x 1.91). Of this, \$91 is the net profit and \$100 is the bet amount.

To convert the bookmaker’s decimal odds into the probability of the event as a percentage plus the margin, you have to divide 100 by the value of the odds. Example: 100/1.75 = 57, i.e. the probability with the margin is 57%.

### Fractional (British) odds

Fractional odds are the ratio of the amount of potential net profit (numerator) to the amount you need to bet to make that profit (denominator). For example, a fractional multiplier of 5/3 tells the player that for every \$3 bet, he will make \$5 in net profit if the bet wins.

To convert the fractional ratio into a decimal ratio, divide the numerator by the denominator and add 1 (one). For our example: 5 / 3 + 1 = 2.66. Another example: 40 / 1 + 1 = 41,0.

### American odds

The value of a positive American odds is the amount of potential net profit at a bet of 100 conventional units. There are two types of American odds shown below:

• positive;
• negative.

For example, a +120 odd means that for every \$100 of bet on sports a player can get \$120 of net profit.

A negative American odds value is the amount one must wager to win 100 notional units. For example, odds -140 means that you need to bet \$140 to get \$100 net profit.

To convert the positive American odds to decimal, divide its value by 100 and add one. For our example: 120 / 100 + 1 = 2.20.

To convert a negative American ratio into a decimal ratio, divide 100 by its value (without the minus sign) and add one. For our example: 100 / 140 + 1 = 1.71.