Katz was born in Manhasset, New York, to Gary and Adrienne Katz, and is Jewish. He has two older sisters, Anna and Natalie, and a younger brother, Austin.
High school
Katz went to Herricks High School in New Hyde Park, New York, where he pitched and played first base and outfield. He threw a 94 mph fastball. He was an All-League selection as a junior, and named All-County, Second Team All-Long Island, 2012 honorable mention Rawlings/Perfect Game Preseason All-America, Perfect Game first team All-Northeast Region, MVP of the Nassau County Exceptional Senior Game, and won the Best Pitcher Award for the RTC Grand Slam Challenge.
College
Katz then pitched for the St. John's Red Storm, attending the school on a baseball and academic scholarship, while majoring in sports management and minoring in business. As a freshman, Katz made 22 appearances, including two starts, and went 1-3 with one save and a 5.33 ERA. During the summer of 2013, Katz pitched in the Hamptons Collegiate Baseball League for the Shelter Island Bucks and the Cape Cod Baseball League for the YD Red Sox. Baseball America named Katz the top pitching prospect in the Hamptons Collegiate Baseball League for that season, and Perfect Game named him the Hamptons pitcher with the best breaking ball. As a sophomore, Katz appeared in 16 games, including nine starts, and went 1-2 with a 3.86 ERA and 39 strikeouts in 42.0 innings of work. On April 2, 2014, Katz started and struck out five in 6.0 scoreless innings of no-hit ball to earn the win as part of a combined one-hit shutout at Wagner. As a junior, Katz appeared in 19 games, including 6 starts, and went 3-1 with a 3.40 ERA and 52 strikeouts in 55.2 innings of work. He threw mostly a fastball, a changeup, and a slider. In March 2015, Katz was named the Big East Conference Pitcher of the Week after striking out 13 batters in 7.0 scoreless innings in a pair of appearances that helped St. John's post consecutive shutouts in a two-game week. Katz, who made one start and one relief appearance, had a career-high 13 strikeouts in 6.0 scoreless frames to earn the win in a start against Fairfield. Katz then added 1.0 shutout inning against Central Connecticut. The lefty surrendered just one hit in his two appearances to limit the opposition to a.048 batting average. Katz was part of the St. John's Red Storm baseball team that won the 2015 Big East Conference Regular Season and Tournament.
Minor leagues
Katz was drafted by the Chicago White Sox in the 27th round of the 2015 Major League Baseball draft. In 2015, at the age of 20, he pitched for the Great Falls Voyagers of the Rookie Pioneer League, and for the Arizona League White Sox of the Rookie Arizona League. He was a combined 0-2 with a 2.20 ERA and 4 saves, as in 32.2 innings he struck out 40 batters. In 2016, he pitched for the Kannapolis Intimidators of the Class A South Atlantic League, and the Winston-Salem Dash of the Class A+ Carolina League. He was a combined 0-1 with a 3.27 ERA and 2 saves, and in 55 innings he struck out 57. On May 20, 2017, the White Sox traded Katz to the Baltimore Orioles for two international pool signing bonus spots valued at over $750,000. Orioles Executive Vice PresidentDan Duquette said of Katz:
"He has a good fastball and excellent strikeout record. A lot of guys like him and they project him to be a major league reliever. We’re going to send him to Frederick.... He showed a good fastball and a really good breaking ball in the . We got a couple good looks at him."
At the time of the trade, Katz had struck out 10.1 batters per 9 innings in his 62-game, 102-inning minor league career. In 2017, pitching for the Kannapolis Intimidators before he was traded, he was 0-1 with a 4.40 ERA, and pitching for the Frederick Keys of the Class A+ Carolina League after the trade he was 3-2 with a 5.57 ERA. Katz pitched in the 2018 season for the Delmarva Shorebirds of the Class A South Atlantic League, for whom he was 3-2 with a 4.26 ERA in 25 games, and for Frederick for whom he was 0-0 with a 4.50 ERA in 5 games. Katz was released by the Baltimore Orioles minor league Class-A affiliate Frederick Keys on October 18, 2018. In late 2018, Katz signed a minor league deal to return to the Chicago White Sox organization, but was released during spring training in March 2019. On April 15, 2019, he was signed as a spring training invitee for the Long Island Ducks of the Atlantic League of Professional Baseball. In 2019 he was 0-0 with a 4.70 ERA over 15.1 innings for the Ducks. He became a free agent following the season. On February 12, 2020, Katz signed a minor league deal with the Kansas City Royals.
Team Israel
Katz was on the roster for Israel at the 2017 World Baseball Classic qualifier, but did not make an appearance during the tournament. Team Israel beat Pakistan, Great Britain, and Brazil, all of which were better ranked. Katz pitched for Team Israel at the 2017 World Baseball Classic, in March 2017. He pitched in 4 games, pitching 3.1 scoreless innings. In October 2018 he became a dual Israeli citizen, partly to help Israel’s baseball team make the 2020 Olympics.
Business venture
Katz, who describes himself as "a big sneakerhead," started a company named Stadium Custom Kicks, which customizes baseball cleats. Among the company's clients are Aaron Judge, Robinson Cano, José Altuve, and a few hundred major leaguers and minor leaguers.
