MLB Park Factors, Measured: What 1,400 Games Say About Every Ballpark
8 min read · Last updated 2026-07-12 · By the SharpBetz team
Every baseball bettor “knows” two things: Coors Field is a launching pad, and pitcher parks kill overs. Both are half-true, and the half that’s false costs people money. So instead of repeating folklore, we measured it — every MLB game in our database this season, grouped by ballpark.
What we measured
Our model’s history database grades every completed MLB game. For each of the 30 parks we computed the average combined runs per game across the 2026 season through July 11 — roughly 45–49 home games per park, about 1,400 games in total. Small samples wobble, so treat single-season numbers as a noisy reading of a real signal; we note where the noise matters.
The 2026 run environments
| Rank | Ballpark | Runs/game (2026) | Sample |
|---|---|---|---|
| 1 | Nationals Park | 11.57 | 49 |
| 2 | Sutter Health Park (Athletics) | 11.51 | 41 |
| 3 | Coors Field | 11.21 | 47 |
| 4 | PNC Park | 10.65 | 48 |
| 5 | Citizens Bank Park | 9.72 | 46 |
| 6 | Wrigley Field | 9.67 | 46 |
| … | league mid-pack | ~8.5–9.5 | — |
| 27 | Progressive Field | 7.96 | 46 |
| 28 | Fenway Park | 7.64 | 44 |
| 29 | Petco Park | 7.55 | 49 |
| 30 | T-Mobile Park | 7.36 | 47 |
Three things jump out.
Coors isn’t #1 this year. The physics of altitude are real — a ball hit at 5,200 feet carries measurably farther, and Coors’ multi-year park factor (~1.28, the highest in baseball) reflects that. But in any single season, who pitches and hits there matters as much as the air. Nationals Park and the Athletics’ temporary home in Sacramento have out-scored it in 2026. If you bet “over at Coors” as a rule, the market beat you to it years ago: the line at Coors is typically set 1.5–2 runs higher than a neutral park. The altitude is priced in. Your edge, if any, is in the residual — and that’s much smaller than folklore suggests.
The spread between extremes is ~4 runs per game. T-Mobile Park to Nationals Park is the difference between a 7.5 total and an 11.5 total. Ignoring park when betting MLB totals is like ignoring the weather forecast when planning a picnic — possible, but why would you?
A “hitter’s park” is not the same thing as a “home run park.” Fenway ranks 28th in total runs this season but inflates doubles off the Green Monster; Oracle Park suppresses home runs more than it suppresses runs. Our model tracks run factor and home-run factor separately for exactly this reason.
Why elevation is the one stable factor
Most park effects are architecture: wall heights, foul territory, outfield dimensions. Those interact with rosters — a lefty-heavy lineup exploits Yankee Stadium’s short right-field porch; a fly-ball pitching staff suffers in Cincinnati. Elevation is different. Thin air affects every batted ball, every game, no matter who is playing. That’s why Coors’ effect has persisted for thirty years while other parks drift up and down the table, and why pitcher ERAs for Rockies pitchers need an adjustment no other staff needs.
How our model uses this
Since July 2026, every SharpBetz MLB projection includes the ballpark’s run factor and home-run factor as model features, alongside the starting pitchers’ rolling form (ERA, WHIP, strikeout rate) and each team’s contact quality. When our model projects a total for a game at Petco, it is not projecting the same game it would project at Coors — and when we show a total pick, the park is already in the number.
One honest caveat, because transparency is the point of this site: park factors are among the stable inputs. Single-game weather (a 15 mph wind blowing out at Wrigley changes everything) is not yet in our model, because no data source provides reliable historical weather to train on. We treat that as a known limitation rather than pretending otherwise — see how our model works for the full list of what’s in and what’s not.
What this means for your betting
- Never evaluate a total without the park. An 8.5 at T-Mobile and an 11.5 at Coors can describe the same two teams.
- Don’t bet park folklore — the market prices it. The Coors over is not free money; it hasn’t been since the 1990s.
- Watch for park-blind stats. A Rockies pitcher with a 4.80 ERA may be a league-average arm; a Mariners hitter with 18 home runs may be a 25-HR bat anywhere else. Park-adjusting is the first step of serious analysis.
- Split runs from homers. For over/under betting, run environment is what matters; HR factor matters more for player props.
All figures from the SharpBetz history database, 2026 season through July 11. Park factor multipliers referenced from public multi-year data. Sample sizes shown; single-season park numbers carry meaningful variance.