1. Jim Parsons As Sheldon Cooper
Since he was a child, Sheldon Cooper has had a genius IQ but little to no social skills. At the beginning of the series, he came off as robotic and crazy, but once his mom had him tested it became clear that he was a genius who found it difficult to relate to us "normal" people. Throughout the series, Sheldon learns to be more human and feel some empathy towards others.
Sheldon stayed true to his neurotic self and continued to annoy people around him until the final episode - which is ironically why he is one of the most loved characters on the show. There is no one quite like Dr. Sheldon Cooper, and the actor who plays him is much different than this oddball scientist. Bazinga!
2. Jim Parsons In Real Life
Jim Parsons landed the role of Dr. Sheldon Cooper in 2007, and for twelve seasons, his career skyrocketed because of the series. He even won a Golden Globe and an Emmy for his performance. Parsons became the highest-paid actor on television by the end of the series where he made $900,000 per episode.
Parsons has lent his voice to movies like Home and narrated the spin-off series, Young Sheldon. He is so much more than just Sheldon Cooper; Parsons is an advocate for LQBTQ+ rights with his husband, Todd Spiewak. He has some new projects in the works that will definitely show his range of abilities as an actor.
3. John Galecki As Leonard Hofstadter
When fans met Leonard Hofstadter in season one, the experimental physicist was known as Sheldon Cooper's roommate and best friend. He put up with Sheldon's ridiculous "roommate agreement" terms but got easily annoyed with his eccentric personality.
Leonard was also a genius, as he got his doctorate by age 24. Throughout the show, fans watched as he became more confident and finally won over Penny, the beautiful neighbor next door. Despite their on and off relationship, Leonard finally puts a ring on her finger by the seventh season.
4. John Galecki In Real Life
Behind Leonard Hofstadter is the excellent John Galecki. Although his acting career began long before the show, he is best known for his part on The Big Bang Theory. Galecki received an Emmy for his performance and many other awards along with the rest of the show's cast.
Most people don't know that Galecki got his start when he had a role on Roseanne in the '90s. Like his co-star, he also earned $900,000 per episode for the last three seasons of the show, making him one of the highest-paid actors on TV. When Galecki was not filming, he played in a duet band and welcomed his first child at the end of 2019.
5. Kunal Nayyar As Rajesh Koothrappali
Although he is a handsome man, the brilliant astrophysicist was not lucky with love when he was introduced to the show in season one. From the first through the sixth season, Raj is plagued by social anxiety, and cannot speak when women are around. He uses his best friend Howard to communicate if a female is present.
Eventually, he gets past this anxiety, but Raj still has trouble with the ladies. Growing up in a wealthy family, Raj was living off his parent's money despite having a job, and they were determined to find him a suitable wife. Raj dates a few women here and there, but he is the only character to not end up with a mate.
6. Kunal Nayyar In Real Life
Like his character, Kunal Nayyar was raised in New Dehli, but the likeness ends there. In real life, Nayyar is suave and has a gorgeous fashion designer wife, Neha Kapur Nayyar, who his character's parents would surely approve of. Like Howard, Sheldon, and Leonard, Nayyar's character appeared in every episode of the series.
By the end of the show, Nayyar was making a whopping $750,000 per episode. Although he had an acting career before the show, the role of Raj boosted him to stardom. Initially, Nayyar was planning to study business at the University of Portland, but his passion for acting took over, and it paid off.
7. Kaley Cuoco As Penny Hofstadter
As an aspiring but mostly unsuccessful actress, Penny is introduced in the first season as the new neighbor who moves across the hall from Leonard and Sheldon. She instantly piques Leonards's interest, and the gang starts spending more time at the Cheesecake Factory where Penny is a waitress.
The Nebraska-born girl tries to make it big in Hollywood but has to waitress to make ends meet. In a group of scientists, Penny is the stereotypical "dumb blonde," but she asks all the questions so that she and the viewers can understand advanced theoretical physics. Fans watched her grow into a responsible adult and saw how she and Leonard navigated their complicated relationship.
8. Kaley Cuoco In Real Life
Before landing the role as Penny, Kaley Cuoco had established herself in Hollywood with her part in 8 Simple Rules. However, through the Big Bang Theory, she became one of TV's highest-paid actresses where she earned $900,000 per episode like Parsons and Galecki.
Like her character, Cuoco dated John Galecki for two years, but it didn't work out; however, Cuoco said they remained on good terms. Besides her acting pursuits, Cuoco is an avid tennis player and equestrian. She actually met her husband, Karl Cook, at a horse show.
9. Simon Helberg As Howard Wolowitz
Howard Wolowitz might have graduated from MIT as an aerospace engineer and became an astronaut, but Sheldon loves to point out that he is not a doctor like the rest of his friends. Despite his overbearing mother who treats him like a child his entire life, Howard turns out to be a confident man.
Although he was seen as creepy when it came to wooing the ladies, Howard eventually settles down when he meets Bernadette. Over the course of twelve seasons, fans saw Howard mature, become a husband and father, and live his dream of going into space even though it turned out to be his worst nightmare.
10. Simon Helberg In Real Life
Although many of us associate Simon Helberg with his character's out-of-date style and pants that are too tight, he is a lot less dorky in real life. Helberg's career took off after he landed the role on The Big Bang Theory, and one of his most recent projects was with Meryl Streep and Hugh Grant for the film Florence Foster Jenkins.
Helberg was making about $750,000 per episode, unlike a few co-stars who earned considerably more. However, Helberg isn't complaining because that is still a huge payday. He is married to fellow actress Jocelyn Towne, and he started working behind the scenes to launch a few new shows.
11. Laura Spencer As Emily Sweeney
Emily Sweeney is a dermatologist who we first meet in season seven as one of Raj's many love interests. Emily has a creepy sense of humor and she is a major fan of horror movies. She scares Raj a little, but she turns out to be one of his longest girlfriends.
At one point, Raj dates Emily and Lucy, but Emily doesn't care. Their relationship gets pretty serious until Raj breaks up with her to pursue a different woman. They eventually get back together when Emily says she is ok if he dates two women at once.
12. Laura Spencer In Real Life
The red-headed beauty simultaneously had roles in The Big Bang Theory and Bones. However, Laura Spencer left to star in a film called Vitality. She wasn't satisfied with her film and television work, so she started doing a web series in 2016, starring as Jane Austen in Edgar Allan Poe's Murder Mystery Party.
Spencer has been out of the acting game since 2017 with her last credited role in Heartland. Today she is mostly active on her Instagram page, where she gives fans updates about her life and shares topics that are important to her.
13. Mayim Bialik As Amy Farrah Fowler
In season three, Amy Farrah Fowler is introduced to the show by Raj and Howard, who find her on a dating site as a possible match for Sheldon. Amy has a doctorate in neurobiology from Harvard, which was inspired by Mayim Bialik's own doctorate. As Penny's self-proclaimed best friend and Sheldon's girlfriend, Amy becomes a regular member of the crew.
Amy has a particularly frumpy style, but hanging out with Penny and Bernadette makes her more open to trying new things. She's understatedly funny, quirky, and it is hard not to fall in love with Amy Farrah Fowler. Throughout the series, we see her breakdown many of Sheldon's walls until they get engaged in the tenth season.
14. Mayim Bialik In Real Life
In real life, Mayim Bialik is just as brilliant as the character she plays on TV. She rose to fame in the '90s when she starred in Blossom and then took some time away from the spotlight to earn her degrees. Not only is Bialik wickedly intelligent, but she also uses her fame to speak out about important issues.
Bialik has been outspoken on topics such as parenting, depression, modesty in Hollywood, and her Jewish faith. She has published many books, including a vegan cookbook and a guide to attachment parenting. Although she has a much better style than her character, they are equally as bright.
15. Melissa Rauch As Bernadette Wolowitz
Dr. Bernadette Rostenkowski-Wolowitz might have a high-pitched voice and a petite stature, but she is not to be messed with. Viewers met Bernadette while she was working with Penny at the Cheesecake Factory and earning her Ph.D. This is where she meets Howard, who asks her out.
Throughout the show, we see how Bernadette is one tough cookie after getting a lucrative pharmaceutical job, having two children, and dealing with Howard's overbearing mother. She even got Howard to move out of his mother's home and start acting like a grown-up.
16. Melissa Rauch In Real Life
Melissa Rauch made a few TV appearances before landing the role of Bernadette on The Big Bang Theory. She appeared on The Office and True Blood, but nothing was as memorable as the brilliant female scientist she perfectly portrayed.
During the eleventh season, Rauch was pregnant in real life, so it was written into the script as an unexpected second child. In real life, she opened up about her struggles with pregnancy and miscarriage. Rauch also wrote and starred in her own movie, The Bronze, about an ex-Olympic gymnast.
17. Alice Amter As Mrs. Koothrappali
Although we never learned Mrs. Koothrappali's first name and she only appeared through video chat, she played a significant role in Raj's life. She proved to be a memorable character from seasons one through five, especially when she divorced Dr. Koothrapali.
Fans gathered that Mrs. Koothrapali was used to her wealthy lifestyle in New Dehli, and she used to be a healthcare worker like her ex-husband. She wants her son to find love, get married, and have children, but that proves to be rather challenging since Raj can't speak to women unless he is drunk.
18. Alice Amter In Real Life
Alice Amter is the actress who portrays Mrs. Koothrapali, and this has been her most memorable role so far. After moving around most of her life from England to Germany, France, Japan, and the United States, Amter decided to settle in LA to start her acting career.
Amter appeared on Hot in Cleavland as Dr. Kapoor, but her acting career has been slow-going. Surprisingly, she and Brian George (Dr. Koothrapali) were only supposed to be on the show one time. However, their characters were so loved that the producers decided to bring them back.
19. Kevin Sussman As Stuart Bloom
Either you love him or hate him as he hates himself; there is no in-between with Stuart Bloom. As the comic book store owner where the boys regularly hang out, Stuart is intertwined in their lives and grows closer to the friend group as the series progresses. He even briefly dates Penny and Amy.
When Howard goes to space, Raj seeks companionship from Stewart, who is just as lonely. He also moves in with Mrs. Wolowitz and takes care of her when Howard moves out. After she passes away, Stewart takes care of Howard and Bernadette's children, and he became a series regular.
20. Kevin Sussman In Real Life
Stewart often describes himself as a depressed man with the body of an 80-year-old, but Kevin Sussman is not like that at all. He got his start when he appeared on Ugly Betty, and The Big Bang Theory pushed his career further.
Sussman didn't earn nearly as much as his co-stars, but he was right behind Mayim Bialik in the number of episodes he appeared in. Since the show wrapped in 2019, Sussman hasn't done much acting, but he probably doesn't need to since he gets residuals every time the show reruns.
21. John Ross Bowie As Barry Kripke
Barry Kripke is one of Leonard and Sheldon's colleagues that everyone loves to hate. He is continually putting Sheldon down, and despite his intelligence, he knows how to rub people the wrong way. He often bothers the guys at work and tried to make them look bad in front of their boss.
He has a speech impediment called rhotacism, which causes Barry to pronounce "R" and "L" like "W." Despite the jokes they make about the way Barry speaks, that doesn't stop him from giving them jabs right back.
22. John Ross Bowie In Real Life
In real life, John Ross Bowie has made a name for himself outside the walls of Cal Tech. Bowie got his start on the sketch comedy circuit and advanced from there. He is not only a performer, but he writes his material as well. Bowie made an appearance in He's Just Not That Into You and Speechless.
While his role in the show wasn't huge, it is definitely one of the parts Bowie is most recognized for. He also worked on a sitcom with fellow Big Band Theory co-star, Kevin Sussman (Stuart). He was also once in a punk band called Egghead.
23. Laurie Metcalf As Mary Cooper
Mary Cooper is Sheldon's loving mother who understands him better than any of his friends. They often call her for advice or help to deal with Sheldon, and she made her first on-screen appearance in season one after Sheldon is fired for disrespecting his boss. The devout born-again Christian is a voice of reason when it comes to Sheldon's confusing ways.
Although her strange home remedies and lectures seem a bit over the top, Mrs. Cooper still comes off as a loving mother to her "Shelly." She is not a series regular, but Mrs. Cooper has appeared or been mentioned in every season of The Big Band Theory. Fans also got to know her backstory better on the spin-off Young Sheldon.
24. Laurie Metcalf In Real Life
Over the course of four decades, Laurie Metcalf made a name for herself in Hollywood even before The Big Band Theory. She has received numerous awards and nominations for her work, and she is most famous for her role in the original Roseanne series.
Metcalf began her career on stage and was nominated for six Tony awards. She is a force to be reckoned with, and The Big Bang Theory is just another success on her lengthy resume. Today she stars on The Connors as Jackie Harris, her reprised character from Roseanne.
25. Christine Baranski As Dr. Beverly Hofstadter
Unlike Mrs. Cooper, Dr. Beverly Hofstadter is not warm or loving towards her son Leonard. As a neuroscientist and psychiatrist, she does not take a warm approach to parenting and often discounts Leonard's accomplishments. Dr. Hofstadter actually respects Sheldon more than her own son.
Beverly only appeared in ten episodes of the show, but she left a lasting impact because of her cold and abrasive attitude. Despite writing many parenting books, she is a controversially terrible mother, but you have to love how she obnoxiously praises Sheldon, only making his ego larger.
26. Christine Baranski In Real Life
In reality, Christine Baranski studied at the prestigious Julliard School and made herself well-known long before The Big Bang Theory. Baranski starred in How the Grinch Stole Christmas, The Good Wife, and the spin-off The Good Fight. She is a 15-time Emmy Award nominee and a two-time Tony winner.
Baranski is just as prim and proper as her on-screen characters, but she is not as cold as some may think. The gorgeous actress has plenty of projects in the works, and she is not slowing down anytime soon. It will be exciting to see what she does in the future.
27. Wil Wheaton As Wil Wheaton
Wil Wheaton plays himself from seasons one to eleven, and for most of that time, he is Sheldon's arch enemy. He first appears in season three when Sheldon joins a tournament to confront Wheaton. He plays a darker more obnoxious version of himself, who used his fame to win people over.
In season five, Wheaton finally makes up with Sheldon and becomes friends with the rest of the main characters. Wheaton softens a bit after the fifth season, and viewers see him take a role in a bad movie alongside Penny to revive his career.
28. Wil Wheaton In Real Life
The real Wil Wheaton grew up on TV as Wesley Crush in Star Trek: The Next Generation. He also had a role in Stand By Me. Since Wheaton played himself, he is not much different than his character, except he has diverse interests like brewing his own beer and blogging.
Wheaton is also a computer and technology fanatic, and he is especially interested in Linux because he is left-handed. He is married to Anne Price, and they have two children. Wheaton got his success early in life, so now he is enjoying trying new activities.
29. Aarti Mann As Priya Koothrappali
Unlike her parents, Priya Koothrapali had a much more prominent role in The Big Band Theory. Introduced in the fourth season, Priya is Raj's younger sister, who is a law student. Behind Raj's back, she and Leonard start dating, but she has a problem with his friendship with Penny.
Despite Leonard briefly cutting ties with Penny to make his relationship work, Priya's parents disapprove of the union, and she has to return to India. Fans saw her via video chat for a few more episodes until she and Leonard had trouble staying faithful and broke their relationship off for good.
30. Aarti Mann In Real Life
Like her character's parents, Aarti Mann's role was supposed to be small, but it was expanded by popular demand. Mann studied theater at NYU and she has had roles in Suits and Scandal. She also had a small role in Grey's Anatomy.
Initially, Mann was nervous to study theater because she said her parents wanted her to go into medicine. However, her siblings encouraged her to pursue acting after they decided to seek out different career paths as well.
31. Brian Posehn As Bert Kibbler
Bert Kibbler might not be an important character, but he is a fan favorite for his sweet yet socially awkward demeanor. While Amy is working in the Cal Tech labs, Bert meets her and develops a crush even though he knows she is dating Sheldon, and doesn't realize Bert likes her.
Bert often makes jokes with rock puns because he is a geologist, but people don't find him funny. Bert's turning point was when he won the MacArthur Fellowship over Sheldon, and you can guess that Sheldon was not pleased.
32. Brian Posehn In Real Life
Brian Posehn is not only an actor, but he is also a musician and a writer. He had roles in New Girl and The Sarah Silverman Program among other small roles. It seemed that Bert was one of his most memorable TV roles.
Posehn was in a band called Relapse Records, and they released their first album in 2006, and this year he released a music-only album. Due to his large stature, Posehn is easily recognizable, making him memorable no matter how big or small his part is.
33. Brian George As Dr. V. M. Koothrappali
Like his ex-wife, Dr. Koothrapali mainly appears via video chat to nag Raj about finding a wife and settling down. Although his son is an accomplished astrophysicist, he is unimpressed since Raj still lives off his money. As a successful gynecologist in New Dehli, he becomes a loveable character throughout the series.
Initially, Dr. Koothrapali was only supposed to make one appearance, but by popular demand, his storyline expanded, and he came back for more episodes. His first physical appearance came in season eight in the middle of his divorce from Raj's mother.
34. Brian George In Real Life
Despite his small role in The Big Bang Theory, the Israeli-Indian actor is a Hollywood veteran who became famous for his role in Seinfeld. After spending most of his life in London, Brian George moved to Toronto to study theater.
Throughout his career, George has had wide success as a voice actor because of his incredible versatility. Although George only had a few prominent TV and film roles, he has made a lasting impression with every single part was given.
35. Sara Gilbert As Leslie Winkle
Leslie Winkler might be the female version of Leonard, but she doesn't put up with Sheldon the same way. Just like Kripke, Leslie enjoys mocking Sheldon and calling him "Dumb a**." She briefly dates Leonard after he figures Penny is out of his league, and after they break up, Leslie has a sexual relationship with Howard.
While she only appeared in nine episodes, Leslie is memorable because of her no-nonsense attitude and misuse of lab equipment to prepare food. She made her last appearance in season nine for Sheldon's birthday party, and it was the show's 200th episode.
36. Sara Gilbert In Real Life
Besides her role in The Big Band Theory, Sara Gilbert is best known for her role as Darlene Conner in Roseanne and The Conners. Gilbert created and formally co-hosted The Talk on CBS. Funny enough, she once dated John Galecki when they were teenagers on the set of Roseanne.
However, it wasn't until 2010 that she came out before The Talk's premiere because she previously chose not to discuss her personal life or sexuality. Gilbert was previously married to singer-songwriter Linda Perry, but they split up in December 2019.
37. Carol Ann Susi (Voice of Mrs. Wolowitz)
Although she never appeared in the show, Mrs. Wolowitz was a considerable part of Howard's storyline. Her character was heard yelling from different rooms asking Howard to do one thing or another. She was known for her loud and obnoxious voice that rang through the house.
The actress behind the voice of Mrs. Wolowitz was Carol Ann Susi, who passed away from lung cancer, which is why Mrs. Wolowitz also passed away on the show. Fans were heartbroken because she had become a favorite character. The cast and crew paid tribute to her with heartfelt messages.
38. Brian Thomas Smith As Zack Johnson
Zach Johnson was Penny's on-and-off-again boyfriend, who first appeared in season three. He was always clueless to the guys making fun of him, and many of their jokes went right over his head. However, fans loved to watch him because he was so handsome.
Zach and Penny accidentally got married because they thought the marriage wasn't real, and it lasted for several years before they realized. They end up having it annulled, which is one of the last times Zach appears on the show.
39. Brian Thomas Smith In Real Life
Brian Thomas Smith's most memorable TV role was on The Big Bang Theory, but he also appeared on Amazing Race. Smith has mostly done commercial acting throughout his career for brands like Taco Bell, Carl's Jr, Honda, Buick, and Heineken to name a few.
Smith has had a few TV and film roles here and there, but nothing as successful as his part in this series. Smith lives a more private life with his wife, and he regularly updates his social media pages so fans can see what he is up to.
40. Kate Micucci as Lucy
Lucy may have been a minor character, but people always remember her for being just as, if not more, socially awkward than Raj. She meets Raj at a singles-only Valentine's Day party, and she feels anxious in social situations, but she is trying to push herself to do new things.
Lucy and Raj briefly date, but she breaks up with him because he is too overbearing. She broke up with him over a text message because he wanted her to meet his friends, which was too much pressure for her.
41. Kate Micucci In Real Life
Kate Micucci is much less awkward than her on-screen character. After her appearance on The Big Band Theory, Micucci turned her talents to voice acting in several animated series and films. You might remember her voice from many Scooby-Doo specials as the voice of Velma.
One of her most significant voice roles was in The Lego Batman Movie as Clayface. In 2018, she married record producer and musician Jake Sinclair, and they live together in New York and Los Angeles.