It’s a new year, and we’re all eagerly awaiting the return of baseball and, in particular, fantasy baseball. The 2025 season is right around the corner, with pitchers and catchers reporting for the Cubs in less than a week, on February 9th (earlier than other teams). Baseball is clearly the best sport for statistics and projections, for a handful of reasons. The long history and sheer quantity of games – 2,430 in each regular season – gives us a treasure trove of data to play with. The 1-on-1 nature of batting and the 1-at-a-time nature of most stats create a perfect environment for projections, where much of what determines success is actually present in the data. As a result, there is a very mature industry of projection systems with good overall accuracy.

At FantasyPros, our job is to help you win your fantasy league, and a big part of that is our various accuracy competitions, which help determine which rankings and projections are worth listening to. Ahead of 2025 drafts, let’s take a look at who had the most accurate projections for the 2024 season.

Accuracy Methodology

There are many ways you could go about evaluating projection accuracy, based on what you’re using the projections for. Our method is tailored specifically towards fantasy advice, meaning we care about playing time and stats like pitcher Wins, which you probably wouldn’t look at if you weren’t focused on fantasy. This has 3 steps:

1. Select the right data: Because we’re here to win fantasy leagues, we mainly care about the standard 5×5 roto categories. For hitters, that means run scored (R), home runs (HR), runs batted in (RBI), stolen bases (SB) and batting average (AVG). For pitchers, we look at wins (W), saves (SV), strikeouts (K), earned run average (ERA) and walks + runs per inning pitched (WHIP). Many of these are counting stats, so we also care about playing time, and thus include at-bats (AB) for hitters, and innings pitched (IP) for pitchers for a total of 12 categories. We then evaluate counting stats on a per-opportunity bases, rather than raw totals, so that we can separate playing time projections from quality-of-play projections. For example, Shohei Ohtani hit 54 home runs on 636 at-bats in 2024. If you projected him to hit 46 homers on 550 at-bats, your at-bat projection missed by 86, but your home run projection was right on the money, correctly predicting his 8.4% home run rate.
2. Evaluate each projection: We ultimately care about how the projection systems stack up against each other, so we measure projection error in context. That 86 at-bat miss for Ohtani might sound like a lot, but it’s actually a bit smaller than the average error for Ohtani’s at-bats. To measure this precisely, we transform each projection error into a z-score, in the context of projections from all sources for the same player and stat. To continue the Ohtani example, last year all sources had an average error of 96.7 for Ohtani’s at-bats, with a standard deviation of 23.3. Thus, your projection that missed by 86 at-bats was (86-96.7)/23.3 = -0.46 standard deviations away from average. Since we’re measuring error, lower is better, so this result is 0.46 standard deviations better than average.
3. Aggregate the projection errors: Another advantage of measuring projection error with z-scores is that it puts every category on the same scale. For a given projection source and stat we will take the average of all their projection error z-scores across the player pool, to get an accuracy score for that stat. Then to judge the best overall projection systems, we add together the scores from each stat.

2024 Fantasy Baseball Projections Accuracy Results

Note that since our z-scores represent projection error, lower is better and zero is average, by definition. Here are the best projection systems of 2024!

A huge congratulations is in order for Derek Carty with his THE BAT X projections earning the #1 spot for 2024! Some context is needed to understand how incredible this achievement is. Projection systems fit into two broad categories: “Original” systems that project their stats from scratch, using historical data and good modeling; and “Consensus” systems, which combine existing original systems, sometimes with an extra layer of weighting and adjustments. This is the 6th year of our competition and two patterns have emerged so far: THE BAT X is consistently the best original system, and consensus systems are more accurate in general, taking the top spot every year until now. In 2024, THE BAT X became the first original system to ever get over that hump and be the most accurate projection system, full stop. It cannot be understated how impressive this is. If you want to learn more about THE BAT X and how it incorporates statcast data for hitter projections, check out the announcement article.

Our second and third place finishers are FantasyPros’ own Zeile Consensus Projections and Ariel Cohen‘s Average Total Cost (ATC) projections! These systems are, in a way, two sides of the same coin. Zeile is a straight-up average of its component systems, with equal weighting. ATC takes the opposite approach, weighting each component system differently for each stat to achieve an optimal mix, leaning on the strengths of each system. Both systems have performed extremely well, with ATC being the #1 most accurate system for the past five years in a row. But this year, Zeile jumped ahead very narrowly by having a slightly bigger lead with pitchers than ATC had with hitters.

Category Results

Here’s the breakdown of every projection system’s performance for each fantasy category:

And Pitchers:

—

Jacob Herlin is a Data Scientist for FantasyPros. You can find him on Bluesky.