The Cheaper by the Dozen franchise consists of a series of films and stage adaptations, based on the real-life events of the Gilbreth family. Based on novels co-written by Frank B. Gilbreth, Jr. and Ernestine Gilbreth Carey, the film series includes two biographical films and three loosely-remade family comedy films inspired by their story. The general plot centers around the lives of parents with a large number of children. Each depicts familial relationships, and working through the challenges that arise with an over-sized household.

Cheaper by the Dozen (1950) was well-received critically and financially, which led to a sequel with Belles on Their Toes (1952). Years later, a fictional loose-remake based on the true-life family was adapted and released in 2003. Though it acquired mild critical reception, its box office returns inspired 20th Century Fox to greenlight a sequel titled Cheaper by the Dozen 2 (2005) which upon release received poor critical response.

A reboot of the franchise was exclusively released on Disney+ on March 18, 2022.

The autobiographical novels Cheaper by the Dozen and Belles on Their Toes were written by siblings Frank B. Gilbreth Jr. and Ernestine Gilbreth Carey, and released in 1948 and 1952, respectively. The books detail their upbringing in a large family of 12 children, as well as the time and motion study techniques by which they were raised.

In Cheaper by the Dozen, the book details the eventful life of the wealthy Frank Bunker Gilbreth and Lillian Moller Gilbreth, in raising a large family. The couple tested and perfected their business practices, helping factories fine-tune their assembly lines for maximum output at minimum cost, and used these skills in their personal lives with their large number of children. The book includes the insights of two of its members, the authors, with the comedy and heart of growing up in an over-sized family. Throughout its pages, the authors seek to teach the importance of hard work. The events and stories within the book are organized topically while the book coming to an abrupt end, portraying the sudden real-life death of their father.

A sequel to the first novel, Belles on Their Toes details the family's continued adventures following the passing of Frank Bunker Gilbreth Sr., with Lillian's attempts to continue perfecting business practices. With the studies rendered and the knowledge she acquired with her husband, Lillian continues to work and provide for her large family. The novel details her role in taking over the profitable business, and the ways in which each family member contributed saving money and maximizing the family income. The Gilbreth family endured a chicken pox outbreak and the influence of an unwelcome boyfriend, and even met the President of the United States.

As a biographical film, the plot details the story of the large Gilbreth family. Frank and Lillian Gilbreth work together in raising 12 children. As both are business professionals and renowned efficiency experts, the trials of raising their children are detailed with comedic situations. The married couple have added assistance from their oldest daughter, who oftentimes acts as a parental figure to her younger siblings. Though Frank and Lillian experience push-back from their children, the family works together to overcome the challenges of everyday life, and to strengthen the couple's company in work experiences. The family’s bond is tested with the sudden passing of Frank, due to heart failure. The family decides to continue to work together, while Lillian takes charge of the business.

After the death of her husband, Lillian Gilbreth works tirelessly to provide for her family, consisting of 12 children. The recent-widow seeks additional work to make extra money. Despite her engineering background, Lillian is challenged by sexist bigotry when applying for various jobs. The family works together, facing difficulties of young adulthood and in helping their mother with the cost of living.