Justin Chemienti believed that the "Big Mac" he bought from McDonald's and the "Bourbon Bacon Cheeseburger" he bought at Wendy's would be as big as advertised.

Chemienti filed a lawsuit against McDonald's and Wendy's on Tuesday, accusing them of deceiving customers with ads that make the burgers look bigger than they actually are.

The proposed class action in Brooklyn Federal Court is similar to a lawsuit filed in March against Burger King Corp in Miami.

Chemienti said McDonald's and Wendy use undercooked beef patties in the ads, making the patties appear 15% to 20% larger than what customers get.

The complaint said the meat shrinks by 25% when cooked and quoted a McDonald's worker who said she preferred using undercooked patties because fully cooked burgers looked "less appetizing."

Chemienti, who lives in Suffolk County, said both chains "materially" exaggerate burger sizes, while Wendy's also inflates the amount of toppings.

The complaint said: "The defendants' actions are particularly troubling now because inflation prices, food, and meat are very high and many consumers, especially low-income consumers, are struggling financially."

McDonald's and Wendy's did not immediately respond to requests for comment, and Chemienti's attorney had no immediate additional comment.

The lawsuit seeks unspecified compensatory and punitive damages for violations such as presenting unrealistic images to attract and deceive consumers since May 2016 and violations of consumer protection laws nationwide.

At an April 28 conference with analysts, McDonald's CEO Chris Kempczinski said low-income consumers may be "increasingly value-sensitive" as rent and gas prices rise.