Calculate Fielding Independent Pitching (FIP) — the metric that isolates pitcher performance from defensive support. A better predictor than ERA.
Last updated: March 2026 | By Patchworkr Team
Typically 3.10-3.20 for MLB. Adjusts FIP to ERA scale for the league.
Fielding Independent Pitching
3.50
Excellent — frontline starter
Well above average
FIP vs ERA: If FIP is lower than ERA, the pitcher may have been unlucky or received poor defensive support. If FIP is higher than ERA, they may have benefited from strong defense or good luck.
| FIP Range | Rating | Prediction |
|---|---|---|
| ≤2.90 | Elite/Cy Young | Top 5% of pitchers, dominant |
| 2.90–3.50 | Excellent | Frontline starter, well above average |
| 3.50–4.00 | Above Average | Solid starter, above league average |
| 4.00–4.50 | Average | Back-end rotation, league average tier |
| 4.50–5.00 | Below Average | Bench/relief consideration likely |
| >5.00 | Poor | Replacement level, urgent improvement needed |
💡 Pro Tip: FIP is more predictive of future ERA than current ERA. Use FIP to identify pitchers whose metrics exceed their results—these are buy-low candidates in trade markets.
Fielding Independent Pitching (FIP) is an advanced baseball statistic that measures a pitcher's performance based solely on outcomes they directly control: strikeouts, walks, hit-by-pitches, and home runs. Unlike ERA (Earned Run Average), FIP excludes balls in play, thereby removing the influence of defensive performance, luck on batted balls, and ballpark factors that affect hit rates but not home runs.
The core philosophy behind FIP is that pitchers have limited control over what happens to balls put in play—whether a line drive becomes an out or a hit depends largely on defensive positioning, fielder skill, and luck. However, pitchers do control whether batters make contact (strikeouts), receive free passes (walks/HBP), or hit balls that clear the fence (home runs). By isolating these "three true outcomes," FIP provides a cleaner measure of pitcher skill.
FIP is scaled to match ERA, making direct comparisons intuitive. A 3.50 FIP suggests the pitcher "should have" a 3.50 ERA given average defense and luck. Research shows FIP is more predictive of future ERA than current ERA itself, making it invaluable for talent evaluation, contract negotiations, and fantasy baseball. Major League front offices heavily rely on FIP and its variants (xFIP, SIERA) to identify undervalued pitchers and make roster decisions.
The coefficients (13, 3, 2) represent the relative run value of each outcome. Home runs cost ~13 times more runs than an average event, while strikeouts save ~2 runs compared to average.
Calculate FIP for a starting pitcher's season:
Rating: Excellent — frontline starting pitcher
This pitcher demonstrates strong command (9 K/9, 2.4 BB/9) with reasonable power allowed (0.9 HR/9)
FIP isolates pitcher skill by removing defense, luck on balls in play, and sequencing. It's more predictive of future performance than ERA. A pitcher with 4.00 ERA but 3.20 FIP likely suffered from bad defense/luck and should improve.
The FIP constant adjusts FIP to the same scale as ERA for easier comparison. It varies by league and year (typically 3.10-3.20 for MLB). Calculate it as: (League ERA - (13×HR + 3×BB+HBP - 2×K) / IP).
Yes, but with caveats. Small sample sizes make FIP volatile for relievers. Also, elite closers often have lower FIPs than ERAs due to high-leverage situations and inherited runners, which FIP doesn't fully capture.
xFIP (expected FIP) normalizes home run rates to league average HR/FB%, assuming some HR rates are luck-driven. xFIP assumes 10-11% of fly balls become home runs, smoothing out statistical noise from small samples.
Some pitchers consistently beat FIP by inducing weak contact, limiting hard-hit balls, or controlling the running game. However, extreme differences between ERA and FIP (>0.5) usually regress toward FIP over time.
The weights (13, 3, 2) come from empirical analysis of run values. Strikeouts prevent ~0.3 runs compared to average ball-in-play outs. The coefficient of 2 scales this to per-9-innings and matches the overall FIP-to-ERA calibration.
FIP accounts for home runs (which ballparks affect), but not for defensive range or batted ball outcomes. Extreme ballparks (Coors Field, Yankee Stadium) still influence FIP through HR rates, though less than they affect ERA.
For fantasy leagues using ERA/WHIP, target pitchers with FIP < ERA (due for positive regression). Sub-3.50 FIP indicates ace potential. Sub-4.00 FIP is solid. Over 4.50 FIP suggests trouble ahead regardless of current ERA.