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. On June 17, 1890, Emile Kinst received U.S. patent 430,388 for the ball-bat, or banana bat, shaped with a curve. The mushroom bat was made in 1906 by Spalding, featuring a larger bat with a mushroom-shaped knob on the handle. The Wright & Ditson Lajoie baseball bat had a normal size barrel but two knobs on the handle. In 1990, Bruce Leinert came up with the idea of putting an axe handle on a baseball bat, filing a patent application for the "Axe Bat" in 2007; it started being used in college and pro ranks, and in 2012 the Marietta College Pioneers won the NCAA Division III World Series using axe-handled bats. In 2025, the New York Yankees popularized a "torpedo bat" design, with the widest diameter lower down than on standard bats, making it 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 (6.6 cm). The "torpedo bat" was designed by Aaron Leanhardt, a field coordinator with the Miami Marlins, who has a Ph.D. in physics from the Massachusetts Institute of Technology.

In Their Own Story

The classroom was silent, save for the scratching outside. Nick kicked open the door, flashlight beam cutting through the dust motes. There it lay, leaning against a chalkboard: an old Louisville Slugger. He wiped the grime from the handle and gripped it tight. It felt heavy, solid. A groan echoed from the hallway. He tightened his grip on the wood, ready to swing.

Reader's Guide

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, a bat is intended to be held so the label faces sky or ground when it strikes the ball during a horizontal swing. Different types of wood will fracture differently. 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. 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 and in 2017 threatened groves in New York's Adirondack Mountains that are used to make baseball bats. 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?

• By regulation, a baseball bat may be no more than 2.61 inches in diameter at the thickest part and no more than 42 inches in length.
• On June 17, 1890, Emile Kinst received U.S. patent 430,388 for the banana bat, shaped with a curve to produce a spinning motion of the ball.
• In 2025, the New York Yankees popularized a "torpedo bat" design, with the widest diameter lower down, making it look like a bowling pin; MLB stated it was legal.
• Babe Ruth used a 40-inch, 54-ounce bat made of ash in 1920, and by 1928 he had reduced it to a 46-ounce club.
• The emerald ash borer has killed more than 50 million white ash trees in the eastern United States, threatening groves used to make baseball bats.