What is Run Value? Definition, Formula, and Example

Run Value Definition

Run Value (RV) measures how many runs a baseball event was worth, expressed as the change in expected runs from before the event to after. Statcast publishes Run Value at the pitch level, the plate-appearance level, and aggregated to a season for hitters, pitchers, and individual pitch types. For pitchers, negative RV is good (they prevented runs); for hitters, positive RV is good (they created them). It is the single most direct way to translate granular event data into the only currency that decides games — runs.

How Run Value Is Calculated

Run Value rests on the run expectancy matrix, a 24-cell table built from decades of play-by-play data. Each cell is keyed by base-out state (eight base configurations × three out totals) and stores the average number of runs scored by the offense from that state to the end of the inning. A simplified slice:

• Bases empty, 0 outs: ~0.50 expected runs
• Runner on first, 0 outs: ~0.86
• Bases loaded, 0 outs: ~2.27
• Runner on first, 2 outs: ~0.22

The Run Value of any event is:

RV = (Run Expectancy after) − (Run Expectancy before) + (Runs scored on the play)

Modern Statcast extends this to the count level, so a 3-0 ball is worth a different RV than a 0-2 ball — falling behind 3-0 jumps the hitter's expected wOBA by a much larger amount than going from 1-1 to 2-1. Each pitch's RV is the change in expected run value of the plate appearance.

Worked Example

A solo home run in a 0-0 count, bases empty, no outs is worth roughly +1.4 runs of RV — the hitter banked one actual run plus a small boost in expectancy for the next batter. A bases-loaded walk in a tie game is worth about +1.0 RV. A called strike three on a 3-2 pitch with the bases loaded and two outs is worth roughly −0.9 RV for the hitter, +0.9 for the pitcher, because it converts a high-leverage state to zero.

In 2024, Tarik Skubal posted approximately −29 RV across his arsenal, leading qualified starters and earning the AL Cy Young. His four-seamer alone was worth roughly −18 runs versus league-average four-seamers thrown in the same counts and locations. Aaron Judge produced about +74 RV at the plate that same season, the highest figure in baseball.

Why Run Value Matters

RV is the bridge between pitch-level analytics and team-level outcomes. Front offices use Run Value per 100 pitches (RV/100) to evaluate individual pitches in an arsenal — if a slider grades at −2.5 RV/100 but a curveball grades at +1.0 RV/100, the pitcher should throw more sliders. Pitching coaches use it to decide which secondary to develop. Hitting coaches use it to flag which counts a hitter is leaking value in. Fantasy and DFS players use seasonal RV as a stickier predictor than ERA or wins.

Limitations and Misconceptions

Run Value is descriptive of what happened, not always predictive of skill. A pitcher who got BABIP-lucky will show better RV than his underlying stuff deserves; a hitter who ran into a hot streak in high-leverage counts will look elite even if his contact quality regresses. Statcast also publishes an expected Run Value (xRV) that strips out batted-ball luck — that's the version to lean on for projection. Finally, RV is count- and context-dependent, so comparing pitchers across very different leverage profiles requires care.

Related Terms

• wOBA
• xwOBA
• FIP
• Stuff+
• CSW%

In Legends Deck

Every pitch in a Legends Deck simulation resolves through a run-value engine that mirrors MLB's run expectancy matrix. Card ratings for individual pitch types are derived from real RV/100 numbers, so a card with a "plus-plus slider" generates the same expected run suppression in-game that the pitch produced on Statcast. This is what makes wOBA, xwOBA, and pitch-mix decisions in the sim track real outcomes instead of arbitrary attack rolls.