How we project MLB home runs

Home runs are rare events

On any given plate appearance, even an elite power hitter rarely clears a 5% chance to hit a home run. Over the course of a full game — typically four at-bats — most hitters sit somewhere between 3% and 12% to go yard. That means HR props live in a high-noise zone where small edges compound and sloppy modeling gets punished.

Our goal is simple: for every batter in tonight's projected lineup, produce a probability of hitting at least one home run in the game. That number becomes the basis for our ranked daily leaderboard and the legs our parlay builder auto-composes.

The categories we consider

We break the problem into a few broad categories of signals. None of these are novel on their own — what matters is how they're weighted, combined, and smoothed against the noise inherent in baseball.

Hitter skill

Every hitter brings a season-long baseline. We look at power-rate indicators — how often a hitter makes hard contact, their batted-ball profile, and how that quality of contact translates into home runs. A hitter with elite exit velocity but a flat swing plane isn't the same bet as someone with moderate EV but a lifted ball.

Platoon matchup

A left-handed hitter facing a right-handed pitcher (or vice versa) usually produces meaningfully different HR rates than same-handed matchups. We factor each hitter's splits against the opposing starter's hand into every projection.

Pitcher profile

Not all pitchers concede home runs equally. Pitchers with elevated fly-ball rates or repertoires that lean on pitches hitters tend to elevate (mid-zone fastballs, hanging breaking balls) concede more HRs. The opposing starter's profile tonight affects every hitter in the lineup.

Park factor

Every MLB stadium plays differently. Some parks inflate home run rates substantially thanks to dimensions, altitude, or the way the ball carries through the local air. Others suppress them. We apply a park-specific adjustment to every projection so a game at Coors Field doesn't share expectations with a game at Oracle Park.

Weather

Temperature, humidity, and wind all affect fly-ball carry. A hot, humid night with outbound wind meaningfully boosts HR rates. A cold, still night cuts them. We pull in-game weather forecasts for every outdoor game and factor them into the final probability.

Recent form

Short-term trends matter, but they're the noisiest input by far. Hitters on a hot streak tend to keep producing in the short term — but chasing recency too hard is how you end up fading a slumping star right before he breaks out. We use recent form as a modifier, not a driver.

Why the rankings matter

The output is a single number per hitter per game: projected HR probability. That's what powers the ranked list you see on our daily HR picks page. Higher probability = better expected value when it aligns with market HR prop odds that are more conservative than our number.

We also surface fair odds in American format alongside each projection, so you can quickly see whether the book's number is sharp, soft, or close to our model. When our implied odds are meaningfully shorter than the book, that's a flag to dig in deeper.

Where home-run modeling goes wrong

A common mistake is to lean too hard on one signal. "He's hot" is a narrative, not a model. "He hit a homer yesterday" isn't predictive. "He's got a great matchup" is meaningless if the park suppresses HRs and it's 45° with inbound wind. Home-run projection is about combining several modest edges into one number — and treating the result as a probability, not a prediction.

Even our best picks on any given night will miss more than they hit. That's the nature of HR props — most individual bets lose, and the edge shows up over volume and across a full season. Bankroll management matters as much as pick quality.

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Rude Bets provides research and projections for entertainment and informational purposes. No gambling advice. Please wager responsibly — see our responsible gambling resources.