Implied Probability From Odds Made Simple for League of Legends Players

You may have heard that League of Legends is a probability game disguised as a brawler. Every time you hover Baron, you are making a quiet percentage call with imperfect information. What are the chances that we will win the 5v5 if we start it now? Is that pick worth the flash? To properly answer those questions, it helps to understand the probabilities involved, but you may find that they are written in an odds format, which can be harder to understand than percentages at first glance.

Fortunately, the technique for converting between odds and percentage probabilities is simpler than most people realize. You won’t need complex tools or lookup tables here, and will likely be able to do most of the sums without ever reaching for a calculator once you know the techniques involved.

Odds as Percentages and a 3-Rep Practice Drill

The key insight is simple: odds are a price for an outcome, and implied probability is the chance that price suggests. You are not trying to predict the future perfectly. You are learning to read the percentage fast enough that the number stops feeling mysterious and starts feeling like data.

Once you have the definition down, the quickest way to lock it in is to practise on real lines, instead of vague examples. Platforms such as Lucky Rebel can help us understand this context. Open Lucky Rebel and treat the odds board like a mechanics drill. Pick two numbers you can see immediately, ideally from different bet types if they are available. Start with a moneyline style line, which is simply “who wins.”

For American odds, negative numbers use abs(odds) / (abs(odds) + 100), so -110 becomes 110 / 210 = 0.5238, or 52.38%. Positive numbers use 100 / (odds + 100), so +150 becomes 100 / 250 = 0.40, or 40.00%. Now, do a second rep on a totals or spread line if you see one. If it is priced at -115, that implies 115 / 215 = 0.5349, or 53.49%. When you compare both sides of the same market, you may notice the implied probabilities sum to over 100%. Don’t worry. This doesn’t mean you’ve made a mistake here. That extra amount is often the site’s built-in margin.

Odds Formats Gamers Actually Run Into

Most people see American odds first, the + and – numbers. The sign tells you which side is being priced as more likely. The conversion is what matters.

American odds:

• Negative: abs(odds) / (abs(odds) + 100)
• Positive: 100 / (odds + 100)

Decimal odds are common in many places and look like 1.80 or 2.50. The conversion is even faster: implied probability = 1 / decimal odds. So 1.80 is 55.56%, and 2.50 is 40.00%.

If you want a League-friendly mental shortcut, think of the conversion as an instant “fight chance” label. You are taking an unfamiliar format and turning it into a percentage you can compare at a glance.

What -110 Means and Why Percentages Can Add Up Over 100

-110 sits close to even. Converted, it implies about a 52.38% chance. That does not mean the outcome is guaranteed. It means the price is treating that side as slightly more likely than heads or tails in a coin flip.

Here is the nuance most explainers miss. In many two-sided markets, both outcomes are priced, and both will have an implied probability. If each side sits around 52%, the total becomes about 104%. That extra is the built-in margin. It is the same reason you should not treat a single teamfight read as destiny. You are working with a priced estimate, not a perfect truth.

This is also where the basic bet labels stop sounding like jargon. Moneyline means “who wins”. Spread means “who covers a points handicap.” Totals means “combined scoring over or under a number.” Once you know what the outcome is, converting to implied probability is the same skill every time.

Why Odds Move During a Game and How to Read the Shift

In League, your percentage read changes when the information changes. A flash gets burned. A jungler shows top. A wave state turns a dive from risky to clean. Odds move for the same reason: new information arrives, the clock changes the situation, and the market updates the price.

The useful habit is to stay in percentage land. Convert the old number and the new number, then look at the gap. Did the implied chance move by 2 points or by 12? That one step cuts through narrative and keeps you grounded in what actually changed.

If you want the same discipline inside ranked, pair probability thinking with emotional control. Calm players can make a call with imperfect information and commit. Tilted players chase certainty that does not exist, and hesitate until the window closes.