What's the Difference Between Bat Speed & Exit Velocity?

Bat Speed is the speed the bat is traveling before impact and Exit Velocity is the speed of the ball off the bat. That's the short answer, but the real answer is a bit of a mystery. It's true that there is a correlation between the two but we did studies in the mid 1990's with a device that measured both bat speed and ball exit velocity at the same time and it was very enlightening. That device is no longer on the market and understanding swing efficiency took a giant step backwards as a result. Today's devices measure Bat Speed or Exit Velocity, but not both, at least those readily available to the public. MLB teams have both, although I'm not sure they fully understand what to do with that information just yet.

You see when you have reliable metrics for both of those speeds, all the questions about swing efficiency are answered. We were working on 'Smash Factor' over 2 decades ago and our findings are what led me to the swing design concepts behind 100/100. There were many players that had higher Bat Speed than ball Exit Velocity. In fact, we set up testing protocols to narrow down all the causes of things like that. Some tests were done using light underweight bats with tiny sweet spots, heavy overweight bats, basketballs, wood bats and aluminum bats, prior to the BBCore bats were introduced. We'll cover those testing protocols in another post but what's crucial to understand is that bat speed is about the energy the hitter can produce. The Exit Velocity is the sum of all the elements of contact, which includes bat speed but by no means, is the end of the list.

There are a ton of 'Leaks' in the body throughout the swing. Our testing was able to narrow down all these different leaks, from shifting the weight at the wrong time, to shortening the swing by various means, by having weak points at the moment of impact and others. As each leak is identified and fixed, the swing efficiency goes up and the Exit Velocity (eV) increases. There is a magic point when the bat speed is at maximum and the Exit Velocity is at maximum and eV is always the same amount faster than the Bat Speed every time. In other words, the 'Smash Factor' is predictably consistent, but only when the swing movements are efficient and the leaks are all plugged up. I should note that this way back device measured Bat Speed at the end of the bat rather than the sweet spot, so it was quite a bit higher then. This post is to point out that there is a very scientific way to identify these leaks and maximize hitters' Exit Velocity in 100% of cases when the leaks are fixed. Over 3 decades, we have averaged over 6 MPH of increased Exit Velocity on Day 1. Like in the case of Rachel Garcia, she added 14% or 11 MPH of Exit Velocity Day 1, with her hitting coach, Todd Budke an ISG Hall of Famer and former USA Men's National Team Captain.

Rachel adding 14% to her Exit Velocity should be impossible, after all, she had just won Freshman of the Year at UCLA. How does the best Freshman in the country add that much in 30 minutes? The only answer is her swing had energy leaks that were costing her a lot of power. Granted, Rachel is not your normal athlete so you may not see 11 MPH of increase as she did. Her body control is through the roof, allowing her to make adjustments immediately, but not every hitter has that level of athleticism. However, every player that we have ever worked with has increased Day 1 just over 6 MPH on average. Most programs promise 2-3 MPH after $600 worth of bats, huge dollars in instruction and 'after 6 weeks or more'. PROOF has always been at the core of all the concepts we teach. You will hit the ball harder the moment you improve the energy leaks in the swing.

This was from the Sports Science episode where Jennie Finch was pitted against a minor league baseball player. They were using the plexiglass as a cover for the sensor measuring force at impact. The baseball was traveling at around 90 MPH and di nothing to the plexiglass. Jennie's 68 MPH softball pitch shattered the plexiglass. This means there is a big difference between the force of a softball vs a baseball thrown harder. This is a major factor in hitting a softball at high Exit Velocities. The softball bats are lighter than baseball bats and the ball is heavier in softball. This makes it more difficult for players to have a high game Exit Velocity in softball and also explains why inefficient swings can get away with some leaks in baseball.

Bat Speed is easily confused with Exit Speed or Exit Velocity. There is a correlation between the two but there are some differences. Bat Speed stays fairly consistent with most hitters, unless the hitter is fooled and they alter their swing to try and make up for the timing mistake. When a hitter is early, you may see their butt go out as they reach out in front of home plate to wave at a change up, which will lower the Bat Speed. When they're late, they will bring the hands in, lean back and try to create space between themselves and the ball, also lowering Bat Speed. When they are on time, their Bat Speed is pretty consistent and significantly higher in some cases. Aaron Judge in 2025 for example, on fastballs and sinkers up and inside versus middle away and middle down, where Exit Velocity is always highest in MLB, Judge loses 13% in Bat Speed. Fastballs at league average 94 MPH or faster up and in, Judge's Bat Speed is 13% less than the middle away versions of fastballs. His Exit Velocity also goes down 13%, from 104 MPH average middle away and down middle, to 90.9 MPH of Exit Velocity up and inside. He shortens his swing and it costs him a lot in Bat Speed and Exit Velocity. Yet, pitchers are still afraid to thrown him up and inside fastballs.

Exit Velocity is the speed of the ball off the bat. Again, there is a correlation with Bat Speed and Exit Velocity but there are a lot of other determining factors. In Ev Hitting, we refer to perfect contact as 100/100/100. This means the batter was 100% on time at contact, 100% of their most powerful swing and 100% perfect contact. Perfect contact is when the sweet spot of the bat hits exactly the center of the ball. All 3 of these things happening together almost never occurs. 100/100/100 is about that perfect moment when all 3 elements come together. Think of this as the boiling point or freezing point. We know that at 32 degrees water freezes, it is very cold at 36 degrees, but only freezes at 32 degrees. The 100/100/100 metric is about that perfect moment that we can measure from, one element at a time.

With that understanding, when a hitter is close to 100/100/100, Bat Speed is typically very high and Exit Velocity is a certain percentage higher than Bat Speed, when the other factors are efficient. The Judge example points this out perfectly.

There were many players that would have higher Bat Speed than Exit Velocity when they first came to see me. This led to a ton of experimental swing tests that I have never seen anyone else do as of yet. One goal all hitters should shoot for is to have the same Bat Speed every swing, but the Exit Velocity will depend on how close to 100% all the other elements are. Our aim is to identify each inefficient swing movement and eliminate them through movement training and other means.

In softball hitting, this smash factor is even more important because the softball is heavier than a baseball and the softball bat is lighter than a baseball bat. This makes it more difficult to get the Exit Velocity higher than the Bat Speed. This is a very misunderstood part of Game Exit Velocity and a major element in Ev Hitting. Softball hitters must overcome the force at impact. Most players have no idea about this factor and so they don't train for it. We made this a main station in the Ev Hitting Programs.

Players should use some type of heavy ball to help train to lock out at impact to lose less energy.

The basketball, making sure to use the age appropriate type ball, is great for simulating the force of a softball thrown at game speeds. This one is a WNBA sized basketball fully inflated. To increase the Game Exit Velocity, players have to learn to lock out correctly to lower the amount of loss of energy at impact. Training with a basketball using Exit Velocity will tell you how strong you are at impact. We'll cover some of the numbers related to the testing in other posts soon.

During that early testing, we often saw Bat Speed increase when players were hitting the basketballs. When they realized the increase with basketballs, their Bat Speed would go up with tee swings as well, then when all the leaks were identified and fixed, the Exit Velocity always increases, 100% of the time. In future posts, we'll cover the Reactionary Quickness testing as well, as it isn't just about increasing Tee Exit Velocity and soft toss. There are tests for finding out exactly the weakest points in any hitter's swing and reactionary ability, but again, more on those later.

Now with that said, how would your swing measure up to these types of very, very specific tests?