Reuben Klamer, an inventor who dreamed up the Game of Life and many other toys and games that entertained young baby boomers in the pre-internet 1950s and ’60s, as well as their children in the ’80s and ’90s, died on Sept. 14 at his home in the La Jolla neighborhood of San Diego. He was 99.

His longtime business associate Beatriz Pardo said the cause was heart failure.

Perpetually cheerful and childlike — friends said he was like an 8-year-old in a grown man’s body — Mr. Kramer had an instinct for trends that would captivate the postwar generation.

His creations included his own version of the hula hoop and a variation on the Erector Set. He came up with a Pink Panther show car built on an Oldsmobile chassis and rode around in it to promote the “Pink Panther” cartoon series.

He also worked closely with television producers and built props for popular shows, including the Starfleet phaser rifle, which could stun or disintegrate living creatures, for the original “Star Trek” series. (He said he had an agreement for the toy rights to the rifle, but it fell apart and his toy phaser was never produced.) He made a special Napoleon Solo gun for “The Man From U.N.C.L.E.” that was so popular, the gun itself received fan mail. (He successfully created a toy version of that one.)

But his best-known invention was the Game of Life, a board game in which, in its original incarnation, the winner was the person who accumulated the most money.

The game, introduced in 1960, reflected the values of the booming suburban culture: Players plodded along a conventional path that took them through school, work, marriage, children and retirement.

Succeeding in the game required minimal strategy and left little to chance — in sharp contrast to Mr. Klamer’s entrepreneurial life, which was full of risk and serendipity. His unpublished memoir, which he finished this year, is titled “Blitz, Sizzle and Serendipity: My Game of Life.”

Serendipity even played a role in the invention of the game. Mr. Klamer had approached the Milton Bradley Company, trying to sell a craft project. That didn’t interest the company’s president, who asked Mr. Klamer instead to develop something to celebrate the company’s 100th anniversary.

As Mr. Klamer wandered through the Milton Bradley archives in Massachusetts, his eye fell on a board game that Mr. Bradley himself had invented in 1860, the Checkered Game of Life, which rewarded virtue and punished vice. Mr. Klamer was captivated by it — not by its puritanical approach, which he would do away with, but by the concept of playing at life, and by its almost infinite marketing potential.

“Something about the word ‘life’ electrified me,” he wrote in his memoir. “It is one of a very few things that every single person experiences, so the market, to put it simply, was literally everyone on earth!”

He sketched out his idea; an artist, Bill Markham, designed it in 3-D, with pop-up buildings; and his friend Art Linkletter, the television host, endorsed it. It was a hit at the 1960 Toy Fair in New York and was soon translated into other languages. At one point, said Ms. Pardo, the executive director of Mr. Klamer’s company, Reuben Klamer Toylab, it ranked second only to Monopoly in worldwide popularity.

By now, Ms. Pardo said, the Game of Life has sold more than 70 million copies in 59 countries and has been the best-selling board game in Japan for more than 50 years. In the United States, it became such a part of the culture that it was inducted into the permanent Archives of Family Life at the Smithsonian Institution in 1981.

The game underwent numerous updates over the years. The early emphasis on money to determine the winner had been “indicative of what sold in that era,” George Burtch, the former vice president of marketing for Hasbro, which acquired Milton Bradley in 1984, said in a phone interview.

As times changed, so did the game, with players encountering midlife crises and being rewarded for good deeds, like recycling the trash and helping homeless people.

“Reuben was very receptive to the changes — in fact he was often the impetus for them — because he was a businessman,” Mr. Burtch said.

“He understood that the Game of Life was not just the game that he invented; it was a brand,” he added. “And for a brand to remain viable, it has to evolve. It has to reflect the market conditions of the time.”

But as Jill Lepore wrote in The New Yorker in 2007, the redesign teams always had a hard time addressing the fundamental criticism of the game — that the only way to reward a player for virtuous acts was with money: “Save an Endangered Species: Collect $200,000. Solution to Pollution: $250,000. Open Health-Food Chain: $100,000.”

And so the company’s 2007 overhaul, the Game of Life: Twists & Turns, was almost existential. Instead of putting players on a fixed path, it provided multiple ways to start out in life — but nowhere to finish. “This is actually the game’s selling point; it has no goal,” Ms. Lepore wrote. “Life is … aimless.”

Reuben Benjamin Klamer, the third of four children, was born on June 20, 1922, in Canton, Ohio, to Jewish immigrants from Romania. His father, Joseph, started a business called Klamer Barrel Company. He drove around to storefronts to buy barrels that had been used for items like jam and pickles, then resold them to a processor for a profit. Reuben often said that he inherited his father’s entrepreneurial drive.

His mother, Rachel (Levenson) Klamer, who worked in a factory, detected something special in Reuben from the start and called him her “million-dollar baby.” Still, she left her husband and family when Reuben was a small child. His father and his new wife, Miriam, raised the children.

Reuben was the first in his immediate family to attend college. He spent a year at George Washington University, but he missed his friends at home and transferred to the Ohio State University in Columbus, where he was taking business courses when the Japanese attacked Pearl Harbor in 1941.

He wanted to join the Navy, but because Ohio State did not have a naval R.O.T.C. program, he had to transfer to the University of Michigan for training. He then attended the United States Naval Reserve Midshipmen’s School in Chicago and graduated in 1943, after which he was sent to the South Pacific. He was granted his bachelor’s degree in business administration in absentia from Ohio State in 1944, while he was still overseas.

After the war, he moved to Southern California and found work as the marketing developer for an air cargo company, where he came up with his first major invention, a collapsible garment rack on which to hang clothing. It allowed New York manufacturers to fly garments to California outlets without folding or packaging them. The racks were collapsed on the way home, making space in the plane to bring back other goods.

After stints in advertising, promotion and sales, Mr. Klamer went to work for the toy division of Eldon Industries in 1951. His chief accomplishment there was the game-changing realization that polyethylene, an unbreakable plastic used for industrial purposes, could be applied to toys, which at that time were made of a plastic that easily shattered.

His experience in plastics enabled him to jump on the hula hoop bandwagon, and he quickly became one of the nation’s largest manufacturers for that short-lived craze. (The Wham-O company introduced the hula hoop but did not have a patent, leaving other companies to imitate it; Mr. Klamer’s was made of the unbreakable plastic and was endorsed by Mr. Linkletter.)

Collaborating with engineers, designers and artists, he developed an estimated 200 toys and other items, including Moon Rocks, Fisher-Price training roller skates, and Gaylord, the walking dog.

Mr. Klamer was married and divorced twice. He is survived by three sons, Jeffrey, Andrew and Jonathan; a daughter, Pamela Klamer Singer; and three grandchildren. His oldest son, Joel, died in 2016.

He was inducted into the Hasbro Inventors Hall of Fame in 2000 and the Toy Industry Hall of Fame in 2005. In 2009 he received the Toy and Game Inventor Expo’s Lifetime Achievement Award.

Mr. Burtch, his friend at Hasbro, said that Mr. Klamer measured his own success by the respect accorded him by the toy industry and by the fact that he was still coming up with ideas for toys in his 90s. By those measures, he said, his friend had succeeded at the Game of Life.