How to Bet MLB Home Run Props

What Is a Home Run Prop?

A home run prop on DraftKings is a yes/no bet on whether a specific batter will hit a home run in a single game.

Example: "Will Shohei Ohtani hit a home run tonight? Yes (-120) or No (-120)?"

If the batter hits a home run at any point in the game (before game ends), the yes side wins. It doesn't matter if it's a solo shot or a grand slam, infield or outfield—one home run = win.

Why Home Run Props Are Popular

1. High variance — home runs are rare and explosive, so odds can be favorable (+150 to +300) 2. Visual appeal — everyone watches for home runs. It's engaging. 3. Available every day — 15 games with 2–3 major hitters each = 30–45 prop options daily 4. Bankroll leverage — if you find a +200 shot that you think is 20% (implied 33%), you're risking 1 unit to win 2

The downside: home run props are one of the least efficient markets because casual bettors love the upside and chase favorites they recognize.

How Often Do Home Runs Happen?

Across MLB:

Average home runs per game: 1.3 per team (1.3 × 2 = 2.6 total per game)
Average home runs per batter per season: 0.3 (for qualified hitters)
Translation: A league-average position player hits a home run once every 3.3 games

But this varies wildly:

Elite sluggers (Judge, Ohtani, Trout): 0.6–0.8 HR per game
Above-average hitters: 0.3–0.5 HR per game
Average hitters: 0.15–0.3 HR per game
Weak hitters: 0.05–0.15 HR per game

A batter with a 15% home run rate (about one every 6–7 games) is a below-average power hitter.

Factors Affecting Home Run Probability

1. Batter Power (Dominant)

This is 60–70% of the result.

Slugging percentage — tells you power production
ISO (Isolated Power) — slugging minus batting average, pure power metric
Exit velocity — how hard the batter hits the ball (50th percentile ≈ 88 mph, 90th ≈ 93 mph)
Barrel rate — percentage of hard-hit balls that are "barrels" (optimal launch angle + exit velo for home runs)

A batter with:

High barrel rate (12%+)
High exit velo (91+ mph avg)
Good season slugging (.500+)

...has roughly 25–30% chance of a home run per game.

2. Pitcher's Fly Ball Rate and HR/9

Some pitchers give up more home runs. This is partly because they're worse, but also because of their pitch selection.

Fly ball pitchers give up more home runs
Ground ball pitchers give up fewer
HR/9 rate is the best predictor (e.g., 1.2 HR/9 vs. 0.8 HR/9)

Facing a pitcher who allows 1.5 HR/9 is dramatically different from facing one who allows 0.7 HR/9.

3. Park Factor

This is huge and often ignored.

Different parks suppress or amplify home runs:

Most HR-friendly: Yankee Stadium, Globe Life (Rangers), Coors Field
Most HR-suppressing: Comerica Park (Tigers), Oakland Coliseum, Petco (Padres)

A 90 mph line drive that's a home run in Yankee Stadium is a double in Oakland. DK usually prices this in, but soft-book lines sometimes don't.

Reference: Here's a list of park factors. Anything above 1.0 is HR-friendly. Below 1.0 suppresses HRs.

4. Handedness (L vs. R)

Some batters hit better against certain pitcher types:

Righty batter vs. LHP: Often better contact rates, similar HR rate
Righty batter vs. RHP: Sometimes exploited by reverse splits

Check splits data (Baseball Reference) before betting. A batter with a .400+ slugging against LHP but .300 against RHP is a "splits guy."

Example: A righty with 25% HR rate vs. LHP but 12% vs. RHP. If he's facing an RHP, don't bet his yes side at +150.

5. Recent Form (Secondary Signal)

A batter with a hot streak (2+ home runs in last 5 games) is slightly more likely to continue. But this is a small effect (2–3% bump).

Avoid chasing after one big game. Use rolling averages.

6. Weather

Temperature: Cold suppresses HRs (ball doesn't carry as far)
Wind: Outfield wind direction matters
Air density: Low humidity (dry air) carries better

A 400-foot fly ball in 75°F humid weather is a home run. In 55°F with 40% humidity, it's a warning-track out.

DK sometimes prices this in, sometimes doesn't. Sharp bettors monitor weather updates before game time and fade bets in cold weather.

Home Run Prop Pricing

Typical odds:

Superstar slugger (Judge, Ohtani, Trout): -130 to -150 (56–60% implied)
Star player (Machado, Soto): -110 to -120 (52–55% implied)
Above-average hitter: -110 (52% implied)
Average hitter: +100 to +130 (50–57% implied)
Weak hitter: +200 to +600 (33% implied or less)

Books use lazy pricing: "This guy hit 0.30 HR/game last season, so -110 implied 52% is close enough."

But the sharp books (Pinnacle) will price:

Cold-weather adjustment
Pitcher-specific factors
Park factor
Recent form

This is where edge lives: finding mispricings the soft books (DK) miss.

Finding Edge in HR Props

Scenario 1: Cold Weather Underdog

Batter normally 0.25 HR/game (implied 25% per game)
It's 45°F and windy
Book still prices at -110 (52% implied)
True probability: maybe 15% in cold weather
Bet: No side (odds favor it)

Scenario 2: Pitcher Factor

Batter has 0.30 HR/game on the season
Facing a pitcher with 1.8 HR/9 (well above average)
Book prices at -110 (52% implied)
True probability: 35–40%
Bet: Yes side (underpriced)

Scenario 3: Park Factor Mispricing

Batter has 0.25 HR/game on the season
Playing at Yankee Stadium (1.15 park factor)
Book prices at -110 (52% implied)
True probability with park factor: 30–35%
Bet: Yes side (underpriced)

Scenario 4: Revenge Narrative (Ignore)

"Player was traded and plays old team tonight"
"Player hit 2 HRs last night, on a heater"
Books often price narratives
Reality: Single-game correlation is tiny (1–2% at most)
Don't bet based on narrative

The Danger: Overestimating HR Probability

This is the most common mistake.

A batter with a 25% season HR rate does not have a 25% chance every game. That's an average. On any given night:

He has maybe 20–30% depending on factors above
Some games it's 15% (cold, bad pitcher matchup, park factor)
Some games it's 40% (warm, soft pitcher, HR-friendly park)

Don't just use season average. Adjust for: 1. Temperature 2. Pitcher HR/9 vs. league average 3. Park factor 4. Handedness matchup

Quick Checklist for HR Props

[ ] What's the batter's season HR rate? (home runs per game)
[ ] What's the pitcher's HR/9 vs. league average?
[ ] What's the park factor? (HR-friendly or suppressing?)
[ ] What's the temperature? (if <55°F, suppress HR odds 3–5%)
[ ] Are there handedness splits I should check?
[ ] Has the batter had recent home runs? (small signal, not dominant)
[ ] What's the implied probability from the odds?
[ ] Am I getting better odds than my estimate?

Bankroll Strategy

HR props are high-variance. A batter with a 25% HR rate has long stretches (10+ games) without a home run.

Use conservative Kelly:

1–2% Kelly per bet (even if you have edge)
Track 50+ bets before scaling up
Expect 20–30% drawdown variance

The house hit rate on HR props is around 45–50% on average. If you're consistently hitting 50%+, you have edge.

Tools to Help

Baseball Reference — season splits, park factors, pitcher HR/9
Weather.com — check game-time temperatures
Savant — exit velo, barrel rate, player home run distances
Vegas lines — track closing lines and compare to DK prices

The Bottom Line

HR props are high-variance, low-efficiency markets where casual bettors blow money on favorites.

If you can systematically adjust for park factor, pitcher quality, and weather, you can find 2–3% edges.

But don't chase the upside. A 25% HR guy at +150 looks tempting, but you need to be 27–28% confident to break even. Most bettors aren't that precise.

Start with 100 bets tracked in a spreadsheet. If you're hitting 50%+, you have an edge. If you're hitting 48%, stop and recalibrate.

The pros treat HR props as a side market, not their primary focus. They're useful for portfolio diversification and leverage, but edge is harder to find than in pitcher strikeouts or moneylines.