Player Valuation Theory
Projected WAR
Teams acquire players based on what they believe those players will do for them in the future. WAR, or Wins Above Replacement, estimates player value in a single number. There are plenty of projection systems that forecast the WAR totals that players will accrue in the future, available on Fangraphs, Baseball Prospectus, and more. I didn't attach MLB players to a single projection model in this app so as to encourage you to use your favorite. Like ZiPS? Great. More of a The Bat X fan? That works too. Want to use your own projection system or make your own crude WAR estimates? Doesn't matter. Every MLB team has a different player value projection model, so when you use this tool to forecast the effects of trades and contracts, choose whichever method you want.
FV
FV, or Future Value, has become the industry standard for high-level prospect analysis. Represented on the 20-80 scouting scale, it grades a prospect's anticipated major league production in one number. Like WAR, there isn't one true all-seeing FV model. Baseball America, Fangraphs, and MLB Pipeline don't have the exact same prospect rankings. When including prospects in a mock trade, value their future production however you choose.
Dollars Per WAR
The $/WAR columns in the trade & contract machines map players' projected WAR values to dollar amounts based on the cost of WAR for bench players, role players, and stars in free agency from 2020-26. Fangraphs published these numbers in a February 2026 study linked below. The app adjusts future seasons for inflation.
What Are Teams Paying For a Win in Free Agency? FanGraphsSurplus Value
The surplus columns in the trade & contract machines multiply the player's cost per WAR by their projected WAR. Subtract their salary from that number and you get surplus value, or the gap between the value of his production and what it costs to pay him.
What Are Teams Paying For a Win in Free Agency? FanGraphsThe Dollar Value of FV Grades
Each prospect's FV grade has a corresponding dollar value based on whether they're a position player or pitcher. Fangraphs supplied the latest conversion rates, along with expected WAR during team control years and star odds for each FV tier, in a July 2026 article linked below. The app adjusts future seasons for inflation.
An Updated Method for Prospect Valuation FanGraphsSalary Before Free Agency
To project salary for players not yet eligible for free agency, Fangraphs applies progressively smaller discounts to the market cost of WAR depending on the player's arbitration status. Using those thresholds (linked below), this app forecasts player salary during their future cost-controlled years based on their projected WAR and arbitration status. Note: Instead of using the league minimum for pre-arb players as Fangraphs did, I ran an exponential regression to determine those discounts based on Fangraphs' arb year parameters and seasons of MLB experience.
The Details of Our New Prospect Valuation Methodology FanGraphsInspired by Lance Brozdowski. Rosters and logos from the MLB Stats API. Inflation projections from the IMF World Economic Outlook.