Batters
- OPS blend: 60% current-season, 40% prior season when both samples are meaningful.
- Power & speed adders: HR and SB contribute small bonuses.
- Playing time: Capped bonus for durability — the guy taking 600 PAs matters.
- Age curve: +8 for age ≤23, sliding down to −3 at 33+.
- Status penalty: IL-60 knocks 10 points, IL-15 knocks 3.
Pitchers
- Starters: ERA vs. 3.80 baseline (capped 1.8–7.2), bulk-innings bonus, WHIP adjustment.
- Relievers: ERA vs. 3.60 baseline with a smaller workload bonus (they're valued lower by design).
- SP/RP split: Determined by innings — 70+ IP in a recent season = SP.
Years of Team Control
Every present-day MLB value is multiplied by a control factor:
- Rental (0 yrs):
×0.70 - 1 yr:
×0.75 - 3 yrs:
×0.85 - Full 6 yrs:
×1.00
Without service-time data in the public API, we estimate control from age and MLB playing time. Rookie-eligible players under 27 get a full 6 years; established veterans lose one year of control per year past 25.
FanGraphs 2026 Trade Value overlay
For the top 50 players on Ben Clemens' 2026 Trade Value series at FanGraphs, we override the model with an 80/20 blend toward FanGraphs' rank. That's why you'll see FG #12 badges — the tooltip includes projected 5-year WAR (ZiPS, 2027–2031). This anchors the top of the market to industry consensus.
What we can't see
- Contracts, AAV, opt-outs, no-trade clauses.
- Medicals, extension talks, clubhouse fit.
- Qualifying offers, luxury-tax implications, international bonus pool.
See also: Team Needs Framework · Trade Grading Rubric.