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The Big Bang Theory Trivia Quiz
The Big Bang Theory follows a group of brilliant but socially awkward scientists — physicists Sheldon Cooper and Leonard Hofstadter and their friends Howard and Raj — whose routine of work, comic books, and takeout is upended when aspiring actress Penny moves in across the hall.
Q1. Which band wrote and recorded the theme song?
Answer: Barenaked Ladies. Chuck Lorre and Bill Prady saw the band in Los Angeles, where Ed Robertson, who had just read Simon Singh's book Big Bang, improvised a rap about the origin of the universe. They asked him to write the theme, and he only agreed after hearing they had not asked anyone else.
Q2. Where do Leonard and Sheldon work?
Answer: Caltech. Both are physicists at the California Institute of Technology in Pasadena, as are Howard, an aerospace engineer, and Raj, an astrophysicist. The real science on the whiteboards came from UCLA physics professor David Saltzberg, who checked scripts and attended every taping for six seasons.
Q3. What do Sheldon and Amy win in the series finale?
Answer: The Nobel Prize in Physics. The last episode brings their careers full circle while also revealing Penny's pregnancy. Their wedding had come one season earlier, in the season eleven finale, after a temporary break-up caused by Sheldon's fear of commitment.
Q4. Why is the elevator in Leonard and Sheldon's building broken?
Answer: Leonard was experimenting with rocket fuel. The season three episode "The Staircase Implementation" reveals the cause. The broken lift is why almost every episode has a stairway conversation. It finally works again in the penultimate episode, which unsettles Sheldon until he decides it simply restores the status quo.
Q5. Where does Howard go right after marrying Bernadette in the season five finale?
Answer: The International Space Station. Howard's wedding coincides with his departure on a space mission. Real NASA astronaut Michael J. Massimino played himself as Howard's fellow astronaut in seasons five and six, and Buzz Aldrin made a cameo in season six.
Q6. Leonard and Sheldon are named after whom?
Answer: Sheldon Leonard, a TV producer and actor. Sheldon Leonard was a long-time figure in television as a producer, director and actor. Leonard and Sheldon, played by Johnny Galecki and Jim Parsons, were the only main characters kept from the original unaired pilot, which Lorre later admitted "sucked" apart from those two.
Q7. In the unaired first pilot, which character played the role that later became Penny?
Answer: Katie. Katie, played by Amanda Walsh, was a "street-hardened" woman whom Leonard and Sheldon invite to share their apartment, alongside a scientist friend called Gilda. Test audiences disliked Katie but liked the two physicists, so the show was retooled with Kaley Cuoco as Penny.
Q8. Who first sang "Soft Kitty" to Sheldon?
Answer: His mother, Mary. Sheldon explains it as the song his mother sang when he was ill, and Penny, Leonard and Amy all end up singing it to him. Young Sheldon showed the origin in February 2018, with Mary singing it to her son while he has the flu.
Q9. Young Sheldon's Mary Cooper is played by the real-life daughter of which actress?
Answer: Laurie Metcalf. Metcalf plays Sheldon's mother on The Big Bang Theory, and her daughter Zoe Perry plays the younger Mary in the prequel. Metcalf, Galecki, Sara Gilbert and Meagen Fay had all worked together on Roseanne, where Chuck Lorre was also a writer.
Q10. Why did the five original stars take a 10% pay cut in 2017?
Answer: To let Mayim Bialik and Melissa Rauch earn more. Galecki, Parsons, Cuoco, Helberg and Nayyar dropped from about $1 million to $900,000 an episode. Bialik and Rauch then signed deals for $500,000 an episode each, up from $175,000 to $200,000. In the first three seasons the leads had earned up to $60,000.
Q11. Which song was the theme of the original unaired pilot?
Answer: "She Blinded Me with Science". The first pilot used Thomas Dolby's hit. That version, made for the 2006–07 season, was never broadcast or officially released, though it has circulated online. Both pilots were directed by James Burrows, and only the reworked second one led to CBS's 13-episode order.
Q12. In which country was an unlicensed copy of the show, The Theorists, made?
Answer: Belarus. Chuck Lorre used his vanity cards to complain about the 2010 show, which had "clones" of the characters and near-translations of the scripts. Legal action looked pointless because the producer was state-run, but once it became known the show was unlicensed the actors quit and it was cancelled.
Q13. Who voiced Howard's rarely seen mother?
Answer: Carol Ann Susi. Mrs. Wolowitz was heard shouting from room to room but almost never seen. Susi voiced her until her death, and in season eight the character dies in her sleep in Florida, which devastates Howard and Stuart, who had been living with her.
Q14. Which actress presented Jim Parsons with his 2011 Golden Globe?
Answer: Kaley Cuoco. Parsons won Best Actor in a Television Comedy at the January 2011 ceremony, with his co-star handing him the award. He also won the Emmy for lead actor in a comedy four times, part of the show's total of seven Emmys from 46 nominations.
Q15. Where did the show rank in the US ratings in its first season?
Answer: 68th. It missed the top 50 entirely in season one and was 40th in season two. A move to Thursdays at 8 p.m. in 2010 helped, and by season eleven it was the number one show. "The Deception Verification" set the series record with 20.44 million viewers.
Q16. Which Nobel laureate made a cameo in season two?
Answer: George Smoot. The astrophysicist was one of many real scientists to appear. Stephen Hawking appeared in seasons five and eight and in the 200th episode, Neil deGrasse Tyson and Brian Greene in season four, and chemical engineer Frances Arnold, another Nobel winner, in season twelve.
Q17. How many episodes did season one end up with?
Answer: 17. CBS ordered 13 episodes in May 2007 and extended to 22 that October, but production stopped on 6 November 2007 because of the Writers Guild strike. While it was off the air, CBS filled the slot with the short-lived sitcom Welcome to The Captain.
Q18. Which former bandmate sued Ed Robertson over the theme song?
Answer: Steven Page. Court documents uncovered in 2015 showed Page claiming he had been promised 20 percent of the proceeds. The full song, 1 minute 45 seconds long, was released in 2007; fans often call it "History of Everything", but the single's cover calls it "Big Bang Theory Theme".
Q19. What does the very last Chuck Lorre vanity card say?
Answer: "The End". Like most Chuck Lorre shows, each episode ends with a one-second card of his writing after the credits, all archived on his website. He used them for everything from jokes to his complaint about the Belarusian copy, and the series finale's card simply reads "The End".
Q20. Which fourth series in the franchise premiered on HBO Max in July 2026?
Answer: Stuart Fails to Save the Universe. Stuart breaks a device built by Sheldon and Leonard and accidentally triggers a multiverse Armageddon. Kevin Sussman, Lauren Lapkus and Brian Posehn reprise their roles, joined by physicist Barry Kripke. It followed Young Sheldon and Georgie & Mandy's First Marriage, and was renewed in August 2026.
The Big Bang Theory quiz answers and explanations
Every question from the quiz above with its correct answer, the story behind it, and where the fact comes from.
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Which band wrote and recorded the theme song?
Answer: Barenaked Ladies. Chuck Lorre and Bill Prady saw the band in Los Angeles, where Ed Robertson, who had just read Simon Singh's book Big Bang, improvised a rap about the origin of the universe. They asked him to write the theme, and he only agreed after hearing they had not asked anyone else.
Source: Wikipedia: The Big Bang Theory
-
Where do Leonard and Sheldon work?
Answer: Caltech. Both are physicists at the California Institute of Technology in Pasadena, as are Howard, an aerospace engineer, and Raj, an astrophysicist. The real science on the whiteboards came from UCLA physics professor David Saltzberg, who checked scripts and attended every taping for six seasons.
Source: Wikipedia: The Big Bang Theory
-
What do Sheldon and Amy win in the series finale?
Answer: The Nobel Prize in Physics. The last episode brings their careers full circle while also revealing Penny's pregnancy. Their wedding had come one season earlier, in the season eleven finale, after a temporary break-up caused by Sheldon's fear of commitment.
Source: Wikipedia: The Big Bang Theory
-
Why is the elevator in Leonard and Sheldon's building broken?
Answer: Leonard was experimenting with rocket fuel. The season three episode "The Staircase Implementation" reveals the cause. The broken lift is why almost every episode has a stairway conversation. It finally works again in the penultimate episode, which unsettles Sheldon until he decides it simply restores the status quo.
Source: Wikipedia: The Big Bang Theory
-
Where does Howard go right after marrying Bernadette in the season five finale?
Answer: The International Space Station. Howard's wedding coincides with his departure on a space mission. Real NASA astronaut Michael J. Massimino played himself as Howard's fellow astronaut in seasons five and six, and Buzz Aldrin made a cameo in season six.
Source: Wikipedia: The Big Bang Theory
-
Leonard and Sheldon are named after whom?
Answer: Sheldon Leonard, a TV producer and actor. Sheldon Leonard was a long-time figure in television as a producer, director and actor. Leonard and Sheldon, played by Johnny Galecki and Jim Parsons, were the only main characters kept from the original unaired pilot, which Lorre later admitted "sucked" apart from those two.
Source: Wikipedia: The Big Bang Theory
-
In the unaired first pilot, which character played the role that later became Penny?
Answer: Katie. Katie, played by Amanda Walsh, was a "street-hardened" woman whom Leonard and Sheldon invite to share their apartment, alongside a scientist friend called Gilda. Test audiences disliked Katie but liked the two physicists, so the show was retooled with Kaley Cuoco as Penny.
Source: Wikipedia: The Big Bang Theory
-
Who first sang "Soft Kitty" to Sheldon?
Answer: His mother, Mary. Sheldon explains it as the song his mother sang when he was ill, and Penny, Leonard and Amy all end up singing it to him. Young Sheldon showed the origin in February 2018, with Mary singing it to her son while he has the flu.
Source: Wikipedia: The Big Bang Theory
-
Young Sheldon's Mary Cooper is played by the real-life daughter of which actress?
Answer: Laurie Metcalf. Metcalf plays Sheldon's mother on The Big Bang Theory, and her daughter Zoe Perry plays the younger Mary in the prequel. Metcalf, Galecki, Sara Gilbert and Meagen Fay had all worked together on Roseanne, where Chuck Lorre was also a writer.
Source: Wikipedia: The Big Bang Theory
-
Why did the five original stars take a 10% pay cut in 2017?
Answer: To let Mayim Bialik and Melissa Rauch earn more. Galecki, Parsons, Cuoco, Helberg and Nayyar dropped from about $1 million to $900,000 an episode. Bialik and Rauch then signed deals for $500,000 an episode each, up from $175,000 to $200,000. In the first three seasons the leads had earned up to $60,000.
Source: Wikipedia: The Big Bang Theory
-
Which song was the theme of the original unaired pilot?
Answer: "She Blinded Me with Science". The first pilot used Thomas Dolby's hit. That version, made for the 2006–07 season, was never broadcast or officially released, though it has circulated online. Both pilots were directed by James Burrows, and only the reworked second one led to CBS's 13-episode order.
Source: Wikipedia: The Big Bang Theory
-
In which country was an unlicensed copy of the show, The Theorists, made?
Answer: Belarus. Chuck Lorre used his vanity cards to complain about the 2010 show, which had "clones" of the characters and near-translations of the scripts. Legal action looked pointless because the producer was state-run, but once it became known the show was unlicensed the actors quit and it was cancelled.
Source: Wikipedia: The Big Bang Theory
-
Who voiced Howard's rarely seen mother?
Answer: Carol Ann Susi. Mrs. Wolowitz was heard shouting from room to room but almost never seen. Susi voiced her until her death, and in season eight the character dies in her sleep in Florida, which devastates Howard and Stuart, who had been living with her.
Source: Wikipedia: The Big Bang Theory
-
Which actress presented Jim Parsons with his 2011 Golden Globe?
Answer: Kaley Cuoco. Parsons won Best Actor in a Television Comedy at the January 2011 ceremony, with his co-star handing him the award. He also won the Emmy for lead actor in a comedy four times, part of the show's total of seven Emmys from 46 nominations.
Source: Wikipedia: The Big Bang Theory
-
Where did the show rank in the US ratings in its first season?
Answer: 68th. It missed the top 50 entirely in season one and was 40th in season two. A move to Thursdays at 8 p.m. in 2010 helped, and by season eleven it was the number one show. "The Deception Verification" set the series record with 20.44 million viewers.
Source: Wikipedia: The Big Bang Theory
-
Which Nobel laureate made a cameo in season two?
Answer: George Smoot. The astrophysicist was one of many real scientists to appear. Stephen Hawking appeared in seasons five and eight and in the 200th episode, Neil deGrasse Tyson and Brian Greene in season four, and chemical engineer Frances Arnold, another Nobel winner, in season twelve.
Source: Wikipedia: The Big Bang Theory
-
How many episodes did season one end up with?
Answer: 17. CBS ordered 13 episodes in May 2007 and extended to 22 that October, but production stopped on 6 November 2007 because of the Writers Guild strike. While it was off the air, CBS filled the slot with the short-lived sitcom Welcome to The Captain.
Source: Wikipedia: The Big Bang Theory
-
Which former bandmate sued Ed Robertson over the theme song?
Answer: Steven Page. Court documents uncovered in 2015 showed Page claiming he had been promised 20 percent of the proceeds. The full song, 1 minute 45 seconds long, was released in 2007; fans often call it "History of Everything", but the single's cover calls it "Big Bang Theory Theme".
Source: Wikipedia: The Big Bang Theory
-
What does the very last Chuck Lorre vanity card say?
Answer: "The End". Like most Chuck Lorre shows, each episode ends with a one-second card of his writing after the credits, all archived on his website. He used them for everything from jokes to his complaint about the Belarusian copy, and the series finale's card simply reads "The End".
Source: Wikipedia: The Big Bang Theory
-
Which fourth series in the franchise premiered on HBO Max in July 2026?
Answer: Stuart Fails to Save the Universe. Stuart breaks a device built by Sheldon and Leonard and accidentally triggers a multiverse Armageddon. Kevin Sussman, Lauren Lapkus and Brian Posehn reprise their roles, joined by physicist Barry Kripke. It followed Young Sheldon and Georgie & Mandy's First Marriage, and was renewed in August 2026.
Source: Wikipedia: The Big Bang Theory
The Big Bang Theory by the numbers
- Seasons
- 12
- Episodes
- 279
- First aired
- 24 September 2007
- Last aired
- 16 May 2019
- Emmys
- 7 wins (46 nominations)
- Season 1 US rank
- 68th
- Most-watched episode
- 20.44 million ("The Deception Verification")
- Top pay per episode
- about $1 million
Source: Wikipedia: The Big Bang Theory
About the The Big Bang Theory quiz
The Big Bang Theory ran for twelve seasons and nearly didn't make it past its first pilot, which had a different female lead and a different theme song. It went on to bring in real scientists, including a Nobel laureate, for cameos and to spin off a whole franchise. The production history is full of facts fans don't usually know, which makes it a fairer test than asking who said "Bazinga."
Questions cover all twelve seasons — Sheldon's quirks and "Bazinga," the friends' science careers, the comic-book and pop-culture references, Penny's arc, and the relationships that grow over time.
What this The Big Bang Theory quiz covers
The quiz follows the gang from the first pilot to the Nobel Prize, but skips the usual Bazinga questions. You get the turning points (the space station, the weddings, the elevator), the people behind the show, from the unaired pilot and its Thomas Dolby theme to the science adviser, the real scientists who cameoed and the pay deals, plus the franchise that kept going after the finale. Each answer below explains the story behind it and links to the source.
How to play
Tap an answer to see the right one straight away, with the story behind it, and check your score at the end. Play Again resets the quiz.
The Big Bang Theory quiz — frequently asked questions
Do I need to understand the science?
No. There are no physics questions. The quiz is about the characters' big moments and the people who made the show.
Does it include Young Sheldon?
A little. One question covers its cast and another the later spin-offs. The rest is about the original series.
How hard is it?
The easy round covers the main storylines; the expert round is about the unaired pilot, ratings, lawsuits and the last vanity card.