The most accurate way to measure pitching velocity is a radar gun set up directly in line with the pitch. A pocket-size radar is plenty for most families, phone apps give a rough estimate, and slow-motion video can give a free ballpark (feet ÷ seconds × 0.68 = mph). For a number you can trust, warm up fully, measure the same way every time, and check a few times a year rather than every bullpen.
At some point every pitching family wants to know the number. How hard does he actually throw? Maybe a coach mentioned it, maybe a teammate posted a reading, maybe your son just wants to know. Getting an honest number is easier than it used to be. Getting a number you can actually trust and compare over time takes a little more care.
Here are the ways to measure pitching velocity, how accurate each one is, and how to use the number without letting it run his development.
Your options for measuring velocity
| Method | How accurate |
|---|---|
| Radar gun | Most accurate. What coaches use. |
| Pocket radar | Good. Plenty for tracking progress. |
| Phone app | Varies. A rough idea only. |
| Slow-mo video | Rough. A free ballpark. |
A radar gun is what scouts and most coaches use. Set up directly behind the catcher (or directly behind the pitcher, aimed at the plate), it gives the most reliable reading.
A pocket-size radar works on the same principle in a small, cheaper device. For a family that wants to check progress a few times a year, it is usually all you need.
Phone apps estimate speed from the camera or from timing you tap in. Some are decent, some are not, and results swing with lighting, angle, and how the phone is held. Treat app readings as a rough idea, not a number to put on a recruiting profile.
The free method: slow-motion video
If you have no device at all, your phone’s slow-motion video can give a ballpark. Film from the side, find the frame where the ball leaves his hand and the frame where it reaches the glove, and use the time between them:
Speed in mph = distance in feet ÷ time in seconds × 0.68
Use the real distance from where he lets go of the ball to the glove, which is several feet shorter than the mound distance, because he releases the ball out in front of the rubber. For example, 50 feet covered in 0.62 seconds works out to about 55 mph. This gives his average speed over the flight, and the ball slows down on the way to the plate, so expect it to read a few mph lower than a radar gun.
“The most useful velocity reading isn’t the highest one. It’s the one taken the same way as last time, so you can see the trend.”
Consistency beats precision for tracking progress.How to get a reading you can trust
- Line it up. Radar reads best straight on. The more the device is off to the side of the ball’s path, the lower the reading.
- Warm up fully first. Readings on a half-warm arm are low and pushing for a number before he’s loose is how arms get hurt. Our guide on warming up before pitching covers the routine.
- Measure the same way every time. Same device, same spot, same setting. That is what makes the trend meaningful.
- Take a handful of pitches, not one. Look at his typical fastball as well as his top reading. The top one gets bragged about, the typical one is what he pitches with.
- Expect devices to disagree. Two radars can differ by 3 to 4 mph on the same pitch. Don’t compare his app reading to a teammate’s showcase gun.
How often to measure
A few times a year is plenty: maybe the start of the offseason, the end of the offseason, and midseason. Measuring every bullpen turns practice into a radar contest, and a kid chasing the gun on every throw starts overthrowing, losing command, and putting more stress on his arm. Never trade a healthy arm for a number.
Game readings are their own thing, too. Many pitchers throw a bit slower in games than in practice, which our guide on why he throws slower in games explains.
What to do with the number
Once you have a reliable reading, compare it to typical ranges for his age. Our average pitching speed by age guide has the chart, and our free Velocity Checker turns his age and speed into an estimated percentile in a few seconds.
Then compare him to himself, not to the kid on Instagram. Progress over months is what matters, and velocity tends to come in jumps rather than a smooth line (more on that in how long it takes to add velocity).
The number tells you where he is. It doesn’t tell you why. Velocity comes from how well his legs, hips, torso, and arm work together, and that is visible on video. A free evaluation breaks his delivery down frame by frame and shows where he is leaking speed he already has. Start his free evaluation.
The bottom line
A radar gun is the most accurate way to measure pitching velocity, a pocket radar is plenty for most families, phone apps give a rough idea, and slow-motion video can get you a ballpark for free. Whatever you use, line it up straight, warm up first, measure the same way each time, and check a few times a year instead of every bullpen. Then use the number to track his progress against himself, and look to his delivery for the why.
Common questions
How do you measure pitching velocity?
The most accurate way is a radar gun set up directly in line with the pitch, behind the catcher or the pitcher. Pocket-size radars are a good, cheaper option for families, phone apps give a rough estimate, and slow-motion video can give a ballpark: distance in feet divided by time in seconds, times 0.68.
Are pitching speed apps accurate?
They vary. Camera-based apps are affected by lighting, angle, and how the phone is held, so results can swing by several mph. They’re fine for a rough idea, but use a radar for any number you want to rely on or share with coaches.
How can I measure pitching speed without a radar gun?
Film from the side in slow motion and count the time from release to the glove. Divide the real release-to-glove distance in feet by the time in seconds, then multiply by 0.68 to get mph. It measures average speed over the flight, so it reads a few mph lower than a radar gun.
Why do radar guns show different speeds?
Devices are calibrated differently and read the ball at slightly different points in its flight, and angle matters too: the more the radar is off to the side, the lower it reads. Two devices can differ by 3 to 4 mph on the same pitch, so compare readings from the same device.
How often should a pitcher check his velocity?
A few times a year is plenty, such as the start and end of the offseason and midseason. Measuring every bullpen tends to make pitchers overthrow, which hurts command and adds stress to the arm.
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