It's been a while since I wrote about gambling. I've mostly just been betting, preparing for a grappling tournament here in Cambodia, which is in a couple of weeks, and keeping my head on other things. But I've been thinking about something worth sharing, and even if it sounds basic at first, implied probability is one of those concepts that's easy to overlook until you've taken enough losses to force you to pay attention.

I threw money at odds like +200 or –150 for a long time without fully understanding what those numbers actually meant. Once I started thinking about them as percentages instead of abstract figures, my decision-making got cleaner. Let me try to explain below...

Positive American Odds

The formula for positive odds is straightforward: implied probability = 100 / (odds + 100).

So for +200, that's 100 / (200 + 100) = 0.333, or roughly 33%. That's the market's estimate of how likely that outcome is to happen. One in three.

Negative American Odds

For negative odds, the formula flips: implied probability = |odds| / (|odds| + 100).

For -150: 150 / (150 + 100) = 150 / 250 = 0.60, or 60%.

For -289: 289 / (289 + 100) = 289 / 389 ≈ 0.742, or about 74%.

The steps for –289 are simple: compute the denominator first (289 + 100 = 389), then divide 289 by 389. That's it.

Why This Changes How You Bet

Thinking in percentages instead of odds is more honest. It’s similar to why casinos use chips instead of cash: the abstraction makes it easier to act without feeling the weight of each decision. Odds do the same thing. Converting them to percentages forces you to see what you’re actually betting on, which makes things clearer when placing bets.

Going forward, I'm scaling back the number of bets I make. I've been spreading too much action across too many risky picks, and that approach hasn't served me well. My plan is to cap myself at ten bets per day and mostly take a position if the implied probability of winning is at least 60 percent, according to my read of the situation. Fewer bets, more conviction per bet.

That said, the real edge in this game still comes from finding spots where your own assessment of probability is higher than what the market implies. If you think something has a 50% chance of happening but the odds only reflect a 30% probability, that's a value bet worth taking. The key is mixing those higher-risk, higher-value plays with the more confident picks so that your overall portfolio of bets is balanced rather than chaotic.

Implied probability won't make you a winner on its own, but it gives you a framework. And frameworks, even simple ones, are how you stop gambling and start making decisions.