Be Your Own Odds Calculator: Why Betting Odds Aren’t Always as They Seem

Last updated: 07 Jun 13:45

Sit down, grab a coffee, and come talk to me about value betting.

“What is value betting?” I hear you cry.


Take a penalty shootout in a football match.

Now, this is a great example for talking about value betting in football because it is one of the only football bets that you can split completely down the middle. There is no “draw” in a penalty shootout, which boosts your odds of winning if you predict the winning side, and it is also the most evenly poised market in the game.

Odds Calculator: Do the Numbers Add Up!?

If you weren’t a bookmaker who is looking to establish a profit margin, and you just decided to become an odds calculator for the fun of it, you would probably say that a price of even-money is perfect for Team A or indeed Team B to win the penalty shootout. Penalty shootouts are essentially a 50-50 lottery, and odds of 1/1 would reflect that.

However, bookies don’t work like that.

You may have noticed that in most cases, bookmakers will price up each team at odds of around 4/5 to win the shootout. Well, this is done by the bookmakers to establish a margin, and clearly doesn’t reflect the actual odds of your chosen bet being successful.

This is where value betting comes into play, and if you become your own odds calculator, you can make a tidy sum in the long-term.

Understand Value Betting to Help Become Your Own Odds Calculator


Value betting, in the context of a penalty shootout, is betting on an event that is more likely to win than the odds given by the bookmaker. Let’s say that in the penalty shootout that Team A was 6/5 to win the shootout. 6/5, when converted as a percentage, represents a probability of around 45%. Now, we know that a penalty shootout victory is 50% in reality, so you have a 5% leeway. In this case, you would place the bet, and if you were to do this over the course of several bets you should be profitable.

Find out more about the importance of betting with the best odds in our Betting Knowledge blog…

Now, bookies don’t make it quite as easy as that, but in order to become your own odds calculator and to become astute in the art of value betting, you need to familiarise yourself with what odds actually mean as a percentage.

For example:

Odds of 1/3 represent a probability of 75.19%

Odds of 4/6 represent a probability of 44.44%

Odds of 16/5 represent a probability of 23.81%

Now, as you can tell from these three examples, there is a huge spread of odds and probability percentages involved in value betting. The trick is to gradually learn these percentages over time so that they become second nature to you.

The only downside to this is that learning the odds and their relative percentage can take a very long time, and finding these value bets is nowhere near as easy as the pie in the sky penalty shootout scenario I talked about earlier.

However, there is a potential shortcut that you can use to help find the hidden gems in the market.

Become Your Own Bookmaker and Your Own Odds Calculator


Time for you to stick it to the man and become the bookie yourself!

Before you do this, pick a sport – and then a division – which you consider yourself to have the most knowledge in. In my case it’s the English Championship, the division below the Premier League.

Next up, take the full set of fixtures from the next set of games for the coming weekend. Have a look at them, take into account the form of the two sides and all the other factors you usually would if you were a real odds calculator.

Then, go with your gut and make your own odds on the markets that you usually bet on. Let me use an example.

Derby County versus Nottingham Forest in the Championship. I think Derby County are a pretty good shout to win this one. They’re at home, they are higher up in the Championship table and are also in better form. I would say that odds of around 8/15 would be about right in this instance for a home win.

But what do we have here?! William Hill have priced the home win at a measly 4/7! 8/15 in the probability stakes is 65.36%, while 4/7 is 63.69%. This means we have a near 2% difference, meaning that we have our first value bet, because the odds on offer from William Hill offer a bigger return than your hypothetical odds.

Congratulations! You’re well on your way to becoming a fully-fledged odds calculator.

If you were to do this across the full set of fixtures you would probably have a small handful of selections each week, which over the course of the season, can produce a very steady income as part of an all-round betting strategy.

Be an Odds Calculator As An Ingredient of Your Betting Mix


I can’t stress this last point enough.

Value betting is by no means a quick buck. It is a succession of marginal gains that over time will build up to create a supplementary income to go alongside your overall betting earnings.

Using’ tracking software will help you greatly in your quest to become a success in the fine art of being an odds calculator. The patterns that will emerge after a sustained stint of value betting will make it apparent as to what types of bets are working and what level of margin is achievable, without being too ambitious.

This is also a skill that requires a lot of practice in order to be successful. Learn what the odds relate to in the form of a percentage and you are halfway there. Once you know the figures inside out, start off small, and in an area you are comfortable in. Make your own odds and compare them with those of the bookies. If your odds are more favourable, then take the big boys on and make a tidy profit.

Still not convinced about’ tracking software? Here are five reasons why you should give it a go.


Teemu Maarela

Esports & Ice Hockey Specialist


Teemu is an enthusiastic Finn who spent his childhood around ice hockey and video games, and he has 10+ years of experience with sports betting industry. Teemu specialises in analysing esports and ice hockey games. He contributes to website in English, writing about his two passions - ice hockey and esports.
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