There are a few quality resources available to interpret PITCHf/x data. FanGraphs is one of them, as we have a comprehensive list of pitch rates and rankings for individual pitchers. FanGraphs player pages also have comprehensive PITCHF/x information on each pitcher along with single game and yearly data.
As for outside sources, the first site I would recommend is BrooksBaseball.net, run by Dan Brooks. Dan, Harry Pavlidis, and Lucas Apostoleris have all come together to create the best website for PITCHf/x data available. The “Player Cards” that were introduced this year offer a tremendous amount of data that was previously unavailable. These three have charted pitches themselves, which also helps ensure the accuracy of the pitches compared to the PITCHf/x system which does so automatically. Taking pitch grips, pitcher’s statements, and other classifications that the system does not account for gives Brooks Baseball’s platform a bit of an edge over any other PITCHf/x resource. Brooks Baseball also carries live data, which is an added aspect that certainly makes it an even more appealing resource.
While Brooks Baseball does have single game data and also has charts available for single games and in their player card, the ability to alter the charts to control for individual pitches is not possible on their platform. That is where Texas Leaguers has a niche.
At Texas Leaguers, you can search for any individual and search a range of dates to evaluate via PITCHf/x. You can get all of the data for a pitcher over a given game, week, month, half, or season if you so wish. In addition, you can also control for individual pitches. You can look to see how effective Dan Haren’s cutter was over the second half of last season and where he most commonly threw it, for instance.
In addition to these three resources, you can see live PITCHf/x results while watching MLB.com’s Gameday or going back into the play-by-play logs after the game to find out which pitch was thrown and the velocity behind the pitch.
PITCHf/x is constantly evolving and I am sure more resources will pop up over the next few years. For now, the ones I have cited are the most prominent websites to analyze pitchers and the pitches they throw.
● Mike Fast’s PITCHF/x Primer – It’s a touch dated since Fast wrote this piece back in 2010, but many of his larger points still hold true. He’s one of the best PITCHF/x analysts the web has yet seen, so it’s worth reading up on his perspective of the data.