Baseball Bat

Verified Timeline

Lore & Background

The bat's form has become more refined over time. In the mid-19th century, baseball batters were known to shape or whittle their own bats by hand, which resulted in a wide range of shapes, sizes, and weights. For example, there were flat bats, round bats, short bats, and fat bats. Earlier bats were known to be much heavier and larger than modern regulated ones. During the 19th century, many experimental shapes and handle designs were tried. Modern bats are much more uniform in design. Innovations include the banana bat, patented by Emile Kinst on June 17, 1890 (U.S. patent 430,388), which was shaped with a curve to produce a rotary or spinning motion of the ball. The mushroom bat, made in 1906 by Spalding, featured a larger bat with a mushroom-shaped knob on the handle for better weight distribution. The Wright & Ditson Lajoie baseball bat had two knobs on the handle, the lower knob at the bottom and a second knob three inches above, to improve grip when choking up. In 1990, Bruce Leinert came up with the idea of putting an axe handle on a baseball bat, filing a patent in 2007; the "Axe Bat" was used by the Marietta College Pioneers when they won the NCAA Division III World Series in 2012, and several MLB players adopted it including Mookie Betts, Dustin Pedroia, George Springer, Kurt Suzuki and Dansby Swanson. In 2025, the New York Yankees popularized a "torpedo bat" design, with the widest diameter lower down, making the bat look more like a bowling pin. MLB stated the new design was legal as it did not exceed the maximum allowed diameter of 2.61 inches. The torpedo bat was designed by Aaron Leanhardt, a field coordinator with the Miami Marlins who has a Ph.D. in physics from MIT.

In Their Own Story

On June 17, 1890, Emile Kinst received U.S. patent 430,388 for the ball-bat, or banana bat. Kinst wrote: "The object of my invention is to provide a ball-bat which shall produce a rotary or spinning motion of the ball in its flight to a higher degree than is possible with any present known form of ball-bat, and thus to make it more difficult to catch the ball, or if caught, to hold it, and thus further to modify the conditions of the game." The mushroom bat, made in 1906 by Spalding, was designed with a larger bat and a mushroom-shaped knob on the handle, enabling the batter to get a better distribution of weight over the entire length of the bat. The Wright & Ditson Lajoie baseball bat had a normal size barrel but two knobs on the handle—the lower knob at the bottom and another knob, also called the shoulder, three inches above the lower knob—designed to have better spacing between the hands. In 1990, Bruce Leinert came up with the idea of putting an axe handle on a baseball bat, filing a patent application in 2007; the Axe Bat started being used in the college and pro ranks over the following years. In 2012, the Marietta College Pioneers baseball team won the NCAA Division III World Series using axe-handled bats. In 2025, the New York Yankees popularized a torpedo bat design, which was made to increase contact hitting. The bat quickly generated media coverage as the Yankees hit a franchise record nine home runs in their second game, the first three home runs being hit on the first three pitches.

Reader's Guide

A baseball bat is divided into several regions. The "barrel" is the thick part of the bat, where it is meant to hit the ball. The part of the barrel best for hitting the ball, according to construction and swinging style, is often called the "sweet spot." The end of the barrel is called the "top", "end", or "cap" of the bat. Opposite the cap, the barrel narrows until it meets the "handle", which is comparatively thin, so that batters can comfortably grip the bat in their hands. Sometimes, especially on metal bats, the handle is wrapped with a rubber or tape "grip". Finally, below the handle is the "knob" of the bat, a wider piece that keeps the bat from slipping from a batter's hands. The "bat drop" of a bat is its weight, in ounces, minus its length, in inches. For example, a 30-ounce, 33-inch-long bat has a bat drop of minus 3 (30 − 33 = −3). Larger bat drops help to increase swing speed, due to less mass per unit length; smaller drops create more power, due to greater momentum to transfer to the ball. Baseball bats are made of either hardwood or a metal alloy (typically aluminum). Most wooden bats are made from ash; other woods include maple, hickory, and bamboo. Hickory has fallen into disfavor over its greater weight, which slows down bat speed, while maple bats gained popularity following the introduction of the first MLB-sanctioned model in 1997. The first player to use one was Joe Carter of the Toronto Blue Jays. Barry Bonds used maple bats the seasons he broke baseball's single-season home run record in 2001, and the career home run record in 2007. In 2010, the increased tendency of maple bats to shatter caused Major League Baseball to examine their use, banning some models in minor league play. Manufacturers position each bat's label over the mechanically weaker side of the wood. To reduce chance of fracture, and maybe deliver more energy to the ball, a bat is intended to be held so the label faces sky or ground when it strikes the ball during a horizontal swing. For bats made of ash, labels will generally be where the grain spacing is widest. For maple bats they will usually be positioned where grain is tightest. Maple bats in particular were once known (circa 2008) to potentially shatter in a way that resulted in many sharp edges, sometimes creating more dangerous projectiles when breaking. Maple bat manufacture evolved significantly, in cooperation with Major League Baseball, paying special attention to grain slope, and including an ink spot test to confirm safest wood grain orientation. Based on consistent anecdotal reports of sales at sporting goods stores, and because of the Emerald ash borer epidemic, maple appears to be displacing ash as most popular new baseball bat material in the United States. Next and rising in popularity is bamboo, which has more isotropic fine grain, great strength, and less weight for a bat of any given size. Within league standards there is ample latitude for individual variation, many batters settling on their own bat profile, or one used by a successful batter. Formerly, bats were hand-turned from a template with precise calibration points but more recently they are machine-turned to a fixed metal template. Historically significant templates may be kept in a bat manufacturers' vault; for example, Babe Ruth's template, which became popular among major-league players, is R43 in the Louisville Slugger archives. Ruth favored a thinner handle than was the norm in the 1920s, and his success caused most to follow. Ruth used an unusually large bat, which he reduced in size incrementally during his career. In 1920 he was using a 40-inch, 54-ounce bat, made of ash, with a slender handle. In 1928 he wrote, "A few seasons ago I used a 54 ounce bat, long and with the weight well at the end. Now I'm using a 46 ounce club--and each season when I have a new set of bats made, I have an addition ounce taken off."

Once the basic bat has been turned, it has the manufacturer's name, the serial number, and often the signature of the player endorsing it branded into it opposite the wood's best side. Honus Wagner was the first player to endorse and sign a bat. Next, most bats are given a rounded head, but some 30% of players prefer a "cup-balanced" head, in which a cup-shaped recess is made in the head, introduced to the major leagues in the early 1970s by José Cardenal; this lightens the bat and moves its center of gravity toward the handle. Finally, the bat is stained in one of several standard colors, including natural, red, black, and two-tone blue and white. In the American major leagues, Rule 1.10(a) states: "The bat shall be a smooth, round stick not more than 2.61 inches in diameter at the thickest part and not more than 42 inches in length. The bat shall be one piece of solid wood." Bats are not allowed to be hollowed or corked—that is, filled with an alien substance such as cork which reduces the weight. Both wooden and metal alloy (generally aluminum) bats are generally permitted in amateur baseball. Metal alloy bats are generally regarded as being capable of hitting a ball faster and farther with the same power. However, increasing numbers of "wooden bat leagues" have emerged in recent years, reflecting a trend back to wood over safety concerns and, in the case of collegiate summer baseball wood-bat leagues, to better prepare players for the professional leagues that require wood bats. Metal alloy bats can send a ball towards an unprotected pitcher's head up to 60 ft 6 in (18.44 m) away at a velocity far too high for the pitcher to get out of the way in time. Some amateur baseball organizations enforce bat manufacturing and testing standards which attempt to limit maximum ball speed for wood and non-wood bats. In high school baseball in the United States, the bat is not permitted to be more than 2+5⁄8 inch.

Did You Know?

• The bat drop is calculated as weight in ounces minus length in inches; a 30-ounce, 33-inch bat has a drop of minus 3.
• Babe Ruth used a 40-inch, 54-ounce bat made of ash in 1920, and by 1928 he had reduced it to 46 ounces.
• Honus Wagner was the first player to endorse and sign a baseball bat.
• The emerald ash borer, an exotic beetle imported accidentally from Asia, has killed more than 50 million white ash trees in the eastern United States.
• In 2025, the New York Yankees hit a franchise record nine home runs in their second game using the torpedo bat, with the first three home runs coming on the first three pitches.