Ray's Ramblings - Spin Rates

Posted on 2018-05-15 13:58 by Ray Flowers

The 2018 Guru Elite MLB All-Star contest is open! Subscribe today and enter for your chance at the Grand-Prize: a trip to the All-Star game in Washington D.C!



Launch angles are all the rage when we talk about batters. When we flip things over to pitchers the bee’s knees are spin rates. In this piece, I will touch on some spin rates baselines and then discuss some interesting facts that pertain to those mound mavens chucking the pelota at batters. 


Major league baseball has a thing called Statcast. You probably know what that is. 

Statcast is a combination of two different tracking systems -- a Trackman Doppler radar and high definition Chyron Hego cameras. The radar, installed in each ballpark in an elevated position behind home plate, is responsible for tracking everything related to the baseball at 20,000 frames per second. This radar captures pitch speed, spin rate, pitch movement, exit velocity, launch angle, batted ball distance, arm strength, and more.

All 30 stadiums installed the technology in 2015 and have been recording data ever since. The camera system and radar allow a never before seen access to data. More than 2.1 million pitches have been tracked across the game the last three seasons allowing terms like launch angle and spin rates to become part of the baseball lexicon. 



From MLB.com

A pitcher's Spin Rate represents the rate of spin on a baseball after it is released. It is measured in revolutions per minute. The amount of spin on a pitch changes its trajectory. The same pitch thrown at the same Velocity will end up in a different place depending on how much it spins. (For instance, a fastball with a high Spin Rate appears to have a rising effect on the hitter, and it crosses the plate a few inches higher than a fastball of equal Velocity with a lower Spin Rate. Conversely, a lower Spin Rate on a changeup tends to create more movement.)



Here’s what the data suggests to this point.

On fastballs more rpm leads to more swinging strikes and fly balls. A lower spin rate tends to generate more grounders.

Two-seamers, otherwise known as sinking fastballs, have less spin rate than 4-seam fastballs. 

Changeups, ready for it?, have less velocity and therefore less spin (duh). 

Curveballs usually have the highest spin rates. 

Sliders are thrown harder than curveballs but have less spin. Sliders have a large difference from top to bottom as players throw the pitch at a variety of speeds. 

Kyle Boddy has worked with his company, Driveline Baseball, to create Bauer Units. He’s worked with Trevor Bauer of the Indians to create the measurement which is PITCH SPING (RPM) / PITCH VELOCITY (MPH). Usually, an increase in velocity leads to an increase in spin rates. Taken from the Driveline website.

This enables us to normalize the spin per the velocity of the pitch. If a pitcher is spinning a fastball at 2400 RPM, that is less impressive at 99 MPH and much more impressive at 89 MPH. Making spin rate more useful over a wide range of pitchers of varying velocities.

The higher the Bauer Unit, the better.



4-Seam Fastball: 2,250 rpm

2-Seam Fastball: 2,125 rpm

Split Finger Fastball: 1,525 rpm

Slider: 2,090 rpm

Curveball: 2,400 rpm

Knucklecurve: 2,280 rpm

Changeup: 1,750 rpm


To access the IN-SEASON PREMIUM CONTENT at Guru ElitePurchase the MLB Guide for 29.99. The package includes Monthly Rankings, Rookie Reports, Bullpen Breakdowns, Pitching/Catching Metric, Player Profiles & much, much more.  You can also pick up the MONTHLY subscription for $9.99 if you would prefer to go in that direction.


There is an attached spreadsheet that breaks down the five main type of pitches thrown by big league pitchers: 4-SEAM FASTBALL SPIN RATES, 2-SEAM FASTBALL SPIN RATES, SLIDER SPIN RATES, CURVEBALL SPIN RATES & CHANGEUP SPIN RATES. We will list Bauer Units for each pitch as well. In future articles, I will dig more into breaking down what the rates mean for specific hurlers on specific pitches. 


*Data from Baseball Savant.


You can hear Ray, Monday through Friday, on SiriusXM Fantasy Sports Radio (Sirius 210, XM 87). Ray is on The Fantasy Drive 7-10 PM EST M/TU/TH/F and 8-10 Weds, and he’s also on the Guru Elite Show Thursday from 2-4 PM EST. You can follow Ray on Twitter at @baseballguys.