With the metal baseball bat selection constantly expanding and changing, selecting the right bat is all about determining the correct size and choosing the bat that makes you, as a hitter, comfortable. Both players and parents should understand the proper way to choose the appropriate length, weight, barrel size, and certification, so you can go to the plate confidently, knowing you’re swinging the perfect bat for you.


1. Not Too Long, Not Too Light

Growing players are the most difficult group to size bats for. As they develop and become aware of their body movement and technique, these players also become able to swing a longer (and heavier) bat.

When the mass of the bat increases proportionally to a player’s strength and swing speed, the force exerted on the ball also increases. The result is greater exit velocity and distance on contact.

Ideally, players should be swinging the heaviest bat that does not cause swing mechanic issues or result in slower swing speeds. The easiest way to determine that sweet spot weight is to demo a certain size before purchase. However, that opportunity may not exist.

Consult the height chart below as a starting point.


2. Know Your Strength

More than height, the more critical factor is a player’s strength. As mentioned previously, you’re looking for the heaviest bat you can control through all parts of the swing.

With “drop weight” being the standard on aluminum bats, the height/weight distribution will remain constant, i.e., a bat that is an inch longer will also be one ounce heavier.

Because the science is not exact on bat selection strictly on a player’s height or weight, Marucci does currently carry -10, -8, and -5 Senior League bats to accommodate those growing players who are transitioning or find themselves in between.


3. Listen to a Pro

Pro Tip: When you don’t have an opportunity to swing, but you can hold the bat, determining the proper bat size is as easy as a simple, one-hand test we call the “Top Hand Test”:

  1. Place both hands in their normal position on the bat with the handle in the fingers, not buried deep into the palm.
  2. Close your eyes, and remove your bottom hand.
  3. If you can control the barrel easily in your top hand with your eyes closed, you may have picked a winner.

Pro Tip: During a full-speed swing, if you or your coach can notice the barrel head dropping limply after the initial hand movement and before contact, the bat is probably too long/heavy.

This inadvertent barrel drop is not only an indication the bat isn’t the correct size, but it also slows the bat through contact, creates an improper adjustment through the swing, and disrupts swing timing and mechanics.

Height 3’5”- 4’0” 4’0”-4’5” 4’5”-5’0” 5’0”-5’5” 5’5”-above
Bat Length 25-26 26-27 27-28 28-30 30-34


4. Look Down The Barrel

One of the often overlooked aspects of bat selection is the barrel diameter. For college/high school players, all BBCOR certified bats carry the same drop weight (-3) and barrel diameter (2 5/8), so really, only the correct length needs to be determined. Other BBCOR facets are all based on preference, such as handle size, weight distribution, and material.

For younger players, the first thing to consider is the league in which you play. Many leagues designate a select bat size or certification to follow. If you’re unsure, ask your coach or league administrator.

If your league allows, the next thing to select is the barrel diameter. Marucci’s Senior League Hex line, for example, is -10, but we offer both a 2 ¾ barrel or a 2 5/8 barrel.

Most players, given the choice, automatically choose the bigger one. The benefits include a slightly larger barrel area, and a more end-loaded feel. With more mass in the barrel, greater force can be exerted on the ball at contact.

However, if you’re not comfortable with an end-load feel, or the extra weight in the barrel disrupts your swing mechanics or Top Hand Test, the slightly thinner barrel is the appropriate choice.