The most popular literary series of all time is by far the Harry Potter series. J.K. Rowling, a British author, has sold at least 500 million copies of her book series, 150 million more than the next best-selling one. Harry Potter and the Sorcerer's Stone, the most popular book in the series, alone sold 120 million copies.

The comparatively small number of novels in the series—there are only seven Harry Potter books—is even more astonishing than the series' sales supremacy. In contrast, the Goosebumps series has 62 primary chapters.

The Harry Potter franchise, which began as a book series, has developed into a global brand thanks to the movies, theme parks, video games, plays, and toys that are all based on Rowling's Wizarding World. The Harry Potter films rank among the highest-grossing films of all time, and the Broadway production of the universe-themed play had a respectable box office performance.

• At least 500 million copies

Author: J. K. Rowling
Cover artist: Mary GrandPré
Country: United Kingdom
Language: English
Genre: Fantasy
Publisher: Bloomsbury Publishing (UK)
Published: 26 June 1997 – 21 July 2007 (initial publication)

No. of books: 7
Website: www.wizardingworld.com

R.L. Stine's Goosebumps series formerly held the record for the best-selling book series of all time before Harry Potter overtook it. The Goosebumps series became a financial powerhouse throughout much of the 1990s after the first book in the series was released in 1992. Stine claims that during some months of the decade, 4 million copies of Goosebumps books were sold.

Goosebumps is still hugely popular all around the world, despite not having the same modern cultural following as Harry Potter. The series has at least 350 million copies in cumulative sales to date. Goosebumps eventually became a huge feature picture, just like its successor as the best-selling book series. The 2015 movie, which starred Jack Black as R.L. Stine, made $158 million worldwide. A sequel was released in 2018.

• At least 350 million copies

Author: R. L. Stine
Cover artist: Tim JacobusMark NagataCraig WhiteBrandon Dorman
Country: United States
Language: English
Genre: Horror, supernatural fiction, thriller, children's literature
Publisher: Scholastic Corporation
Published: Original series: July 1992 – December 1997Spin-off series: October 1994 – February 2000; April 2008 – present
No. of books: 240

The Perry Mason books by Erle Stanley Gardner, which were first released in 1933, caused a cultural sensation and eventually served as the basis for a popular television program. The 82 novels in the series have collectively sold close to 300 million copies.

Before becoming a writer, Gardner worked as a lawyer. He was recognized for his fast-paced yet complex stories that let his star lawyer delight readers. When Gardner passed away in 1970, he was the best-selling American author of the 20th century, so Mason was undoubtedly entertaining enough. Gardner's publisher stated that they were selling 20,000 volumes per day and 2,000 books per hour outside of the United States in the 1960s.

• 300 million copies of the series’ 82 novels

Author: Erle Stanley Gardner

Language: English

Published: 1933

No. of books: 82 novels

Children's book series Berenstain Bears was started by the late Stan and Jan Berenstain and carried on by their son Mike Berenstain, who took over full authorship in 2012 after Jan's passing. The stories are told from the perspective of a family of anthropomorphic grizzly bears, who typically acquire a moral or safety lesson along the way.

The Big Honey Hunt, the first Berenstain Bears book, was published in 1962, and since then, the series has expanded to over 300 books, with sales of almost 260 million copies across 23 languages. The Berenstain Bears brand has grown significantly beyond the books to include two television programs as well as a wide range of other merchandise and licenses. The series has faced criticism for its alleged sugary tone and formulaic storytelling despite decades of success and multiple awards.

The series, which Stan and Jan Berenstain wrote and drew, has been a staple of children's book shelves for many years. Following the deaths of the two original inventors in 2005 and 2012, their son Mike Berenstain continued the family legacy. The younger Berenstain is still producing books featuring the Berenstain Bears today.

• Almost 260 million copies across 23 languages

Author: Stan and Jan Berenstain
Country: United States
Language: 23 languages
Published: 1962
No. of books: over 300

The Choose Your Own Adventure book series, which was first released in 1979, had an explosion in popularity among kids in the 1980s, when it became a bestseller. The 184 novels in the series, which was first published by R.A. Montgomery, were written by 30 different authors. The books in the series sold 250 million copies before falling out of print in 1999.

In the Choose Your Own Adventure series of children's game books, the reader assumes the position of the protagonist and makes decisions that affect the actions of the main character and the resolution of the tale. Each story is told from a second-person point of view. The "Adventures of You" series, which began with Packard's Sugarcane Island in 1976, was based on an idea developed by Edward Packard and was published by Constance Cappel and R. A. Montgomery's Vermont Crossroads Press.

The Choose Your Own Adventure books were renowned for their ground-breaking design, which let readers choose what happened to the book's protagonists. The book's plot and conclusion would change according to the reader's decision. Sometimes the main character would gain from the reader's decision. In other cases, the reader could condemn the character to an unfortunate outcome.

Genre: Children book
Published: 1979–1998 (original series)
No. of books: 184 (original series)