How to read odds

Understanding betting odds is key to successful betting. If you do not understand betting odds and the probabilities that they imply, you will struggle to succeed in betting on sports long term.

You don’t need to be a math genius to succeed in betting on sports, but if you do not understand what betting odds reflect, you are setting yourself up for failure.

What are betting odds?

Betting odds represent the probability of an outcome occurring and the return (profit) you will receive if your bet is a winner. The probability represented by betting odds is often referred to as the ‘implied probability’. Understanding the implied probability is crucial. Why? Because you should only bet when you believe the probability of an outcome occurring is higher than the implied probability.

Let’s consider an example. Let’s say the New York Giants are facing the Washington Redskins in a regular season NFL game. The Giants are at odds of -110 to cover the betting line of -3.5 points. The probability implied in the odds -110 is 52.4%. You’ve done your research and have determined the Giants are a 60% chance to cover the -3.5 betting line. As 60% is greater than 52.4%, you have found what is commonly referred to as a ‘value bet’.

However, if following your research you determined that the Giants are only a 45% chance to cover the -3.5 points betting line, the implied probability of the odds is greater than your determined probability. You have not found a value bet and should not place a bet on the Giants.

Shortly we will show you how to calculate the implied probability reflected in betting odds, but first let’s discuss the most popular odds format in the U.S,  American Odds.

Decimal odds spreadsheet

How to read American odds

There are three popular odds formats:

  • Fractional Odds
  • Decimal Odds
  • American Odds

For the purposes of this article, we will focus on American odds. But if you would like to learn more about betting odds and alternative odds formats, read the bettingexpert guide to converting betting odds.

American odds are presented as either positive or negative odds. The following is an example of American odds for an NBA game between the Boston Celtics and Chicago Bulls.

Boston Celtics+130
Chicago Bulls-140

Positive American odds reflect your profit should you bet $100 and are displayed as:

Boston Celtics+130

In this instance, if you bet $100 on Boston to win the game and they win, you will receive a profit of $130.

Negative American odds reflect the amount of money you would have to bet in order to win $100 and are displayed as:

Chicago Bulls-140

In this instance, if you bet $140 on Chicago to win the game and they win, you will receive a profit of $100.

How to calculate implied probability

As previously stated, understanding and calculating the implied probability in betting odds is key to long-term betting success.

So how do we calculate the implied probability in American odds?

Calculating the implied probability in positive American odds is quite simple:

Implied probability = 100 divided by (positive odds + 100)

So in our example, the Celtics are at odds of +130 to win the game. What is the implied probability of these odds?

Implied probability = 100 divided by (130 + 100)
Implied probability = 100 divided by 230
Implied probability = 0.4348

So the implied probability of the Celtics winning the game is 0.4348 (or 43.48%). In this instance, the bookmakers believe the Celtics are a 43.48% chance of winning the game.

Calculating the implied probability in negative American odds is fairly straightforward:

Implied probability = negative odds divided by (negative odds – 100)

So in our example, the Bulls are at odds of -140 to win the game. What is the implied probability of these odds?

Implied probability = -140 divided by (-140 – 100)
Implied probability = -140 divided by -240
Implied probability = 0.5833

So the implied probability of the Bulls winning the game is 0.5833, or 58.33%. In this case, the bookmakers see the Bulls as a 58.33% chance of winning the game.

Value bets

As stated earlier, the key to successful betting is to bet only when there is value. In our example, we should only bet on either the Bulls or Celtics if we determine that they are a better chance to win the game than what the odds represent.

If we believe the Celtics are a better chance to win than 43.48%, we should bet on them. If we believe the Bulls are a better chance to win than 58.33%, then likewise, we should bet on them.

Understanding betting odds is crucial to long-term betting success. Possessing an intimate grasp of betting odds and their implied probabilities is fundamental to profitable betting.

Upcoming games: Los Angeles Rams-Kansas City Chiefs

Los Angeles Rams - Kansas City Chiefs
2018-11-20 02:15 | NFL
HT / FT will end with 2/1 - odds 6.50
N F L, national football league, the competition that the fans in United states follow with interest. This is a match between two squad very strong and for me this is a match with many point. The home team is los angeles rams, team that play very well at home and for me could do a great season. Now the road team is kansas city, team very interesting, wit a good players and this match is very strong to bet. The home team have a record of 9 win and 1 lost, the road team have a record of 9 win and 1 lost. For this reason, I believe in a match very difficult, and I decide to bet to 2 fist half, 1 finals
Los Angeles Rams - Kansas City Chiefs
2018-11-20 02:15 | NFL
Kansas City Chiefs AH +4.00, full event - odds 1.81
los angeles rams is at the estadio azteca playing with kansas city chiefs in the american national football league. Kansas city chiefs are very good scorers and very offensive in their game play. So i expect the chiefs to score more due totheir play style. Los angeles rams is not an easy opponent but the chiefs are also very offensive thus i believe they will score more in this game. I believe this going to be tough and there will not be a very large point difference between these two good teams. Therefore i will pick the kansas city chiefs +4 as my pick since the chiefs are high scoring even if they are visiting los angeles rams
Los Angeles Rams - Kansas City Chiefs
2018-11-20 02:15 | NFL
Los Angeles Rams - Kansas City Chiefs: under 59.5 points, full event - odds 2.36
A game of the American football between two in form teams this game is certainly a test for tge best team here since both teams are in an outstanding wins with records of 9-1-0 respectively. both teams are currently in win streak though and I think will certainly want to play a consious game with thier best form here. I think both teams will invest in the defense heavily in this game and probably we could expect a very low score game from both teams. both teams have been outstanding so far with thier amazing form but with respect to thier h2h they have not scored up to 50 score points. so bet here would be on the under 59.5.
Los Angeles Rams - Kansas City Chiefs
2018-11-20 02:15 | NFL
HT / FT will end with X/1 - odds 26.00
Another Prediction to this game where I think since it's a both team Favourites game here we could see a possible draw game here in the first half of the game and possibly ba win here for the Los Angeles Rams in the 2nd half and at full time score. the home team are kinda Favourites here considering they will be on the front of thier fans who will certainly be at thier back in support. Both teams are in very good form so a first half draw is very possible with a win coming for either one of the team though with home team much more Favourites for the win. HT/ft of draw/loss Angeles rams is my take.
Los Angeles Rams - Kansas City Chiefs
2018-11-20 02:15 | NFL
HT / FT will end with - odds 40.00
Another Prediction to this game where I think since it's a both team Favourites game here we could see a possible draw game here in the first half of the game and possibly ba win here for the Kansas City chiefs in the 2nd half and at full time score. the home team are kinda Favourites here considering they will be on the front of thier fans who will certainly be at thier back in support. Both teams are in very good form so a first half draw is very possible with a win coming for either one of the team though with guest team also much more Favourites for the win. HT/ft of draw/Kansas City chief is my take.
Last modified: 2018-11-19 09:42:04 UTC+2

Betting Against The Odds

When you bet for the underdog, it is called betting “against the odds.” For example, if odds are +300 for the Bears this Sunday, then it is three times more likely that they will lose than win. Odds of +300 indicate that if you bet $100, you will win $400, the original amount of your bet plus the profit.

In Summary

Betting odds represent the probability of an event to happen and therefore enable you to work out how much money you will win if your bet wins. As an example, with odds of +400, for every $1 you bet, you will win $4. There is a 20% chance of this happening.

How To Read Odds
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