Lisa Simpson IQ

Lisa is a properly gifted child. She is promoted a grade after acing an achievement test, gets invited to Springfield's Mensa chapter, and is the person in town most likely to smell a con. Her stated 159 works as a headline, but the show mostly demonstrates a hard-working, well-read student rather than an exceptional problem solver. Her lapses decide it. She sabotages a rival's diorama, she tries to sabotage her baby sister when outscored, and her case for the truth keeps outrunning her evidence. Gifted, short of the 150s.

Age-normed for an 8-year-old.

Six ratings out of ten, each based on what is shown on the page or screen. They are how the estimate is built, not a substitute for it.

Deduction7/10

Solving new problems from thin information

Strategy4/10

Multi-step plans that account for other minds

Knowledge8/10

Depth and breadth of what they know

Invention4/10

Building or devising something genuinely new

Adaptability5/10

Recovering when the plan breaks

Reading people5/10

Understanding what other people want and will do

1. Skipping to the third grade

   Moderate evidence

   Bart vs. Lisa vs. the Third Grade, Season 14

   The family buys a satellite dish and Bart drifts into television. Lisa studies for an achievement test instead and earns a place in third grade, where she lands in the same class as Bart, who has been demoted. She finds the move socially hard, and Skinner eventually returns both children to their original grades. The advancement is a straightforward academic marker for an eight-year-old and the difficulty afterwards is realistic for a gifted child. It supports gifted, not more, because a test result is all it proves.

2. Refusing the angel skeleton

   Strong evidence

   Lisa the Skeptic, Season 9

   When a winged skeleton is dug up at a construction site and the town decides it is an angel, Lisa asks a scientist to examine it and later compares belief in angels to belief in leprechauns, which costs her socially. The skeleton turns out to be a publicity stunt for the new Heavenly Hills Mall. She is right about the science and right about the con, in a town that believes otherwise. That is genuine scepticism under pressure, and the strongest single showing of her reasoning.

3. Building a doll to change minds

   Moderate evidence

   Lisa vs. Malibu Stacy, Season 5

   Lisa objects to the talking Malibu Stacy doll's phrases and tracks down its original creator, Stacy Lovell. Together they design the Lisa Lionheart doll as an alternative for girls. It draws press attention, then loses shoppers to a redesigned Malibu Stacy with new hats. The campaign is organised, persuasive and partly successful, and it comes closest to invention in her file. The commercial result is modest, which is a fair reminder that her strengths are ideas and argument, not management.

4. Proving Jebediah was a pirate

   Moderate evidence

   Lisa the Iconoclast, Season 7

   Preparing an essay for Springfield's bicentennial, Lisa finds a confession among Jebediah Springfield's belongings. She then matches a torn piece of it to details in a Gilbert Stuart portrait of Washington, which establishes that the town's founder was a pirate who once tried to kill him. It is archival detective work and it lands, though the puzzle is set up by the script. She then decides the myth is worth more to the town than the truth, a judgement about people rather than evidence.

5. Invited to Mensa

   Moderate evidence

   They Saved Lisa's Brain, Season 10

   After a letter attacking Springfield's anti-intellectualism, Lisa is invited to the local Mensa chapter with Skinner, Comic Book Guy, Dr. Hibbert and others. Membership needs a score in roughly the top two percent, so it is a solid floor for her ability. When Mayor Quimby leaves, the group takes over the town and its geniocracy collapses into metric time, reproduction rules and an angry mob. The episode's point is that being gifted is not the same as being wise, and Lisa is the one who sees it.

• Sabotaging MaggieSmart & Smarter, Season 15When Maggie's IQ result of 167 tops Lisa's 159, Lisa panics about losing her role as the smart one and teaches her baby sister false information. Marge catches her, Lisa has a nightmare, and she runs to the Natural History Museum. A mind that reacts to being outscored by a toddler with sabotage is showing a large emotional blind spot, and it is the clearest case of her intelligence being outrun by her pride.
• Framing Allison's dioramaLisa's Rival, Season 6When new classmate Allison Taylor outshines her, Lisa lets jealousy get the better of her. With Bart's help she replaces Allison's diorama with a cow's heart, and Skinner humiliates the other girl. Guilt then sends Lisa to retrieve the real diorama, and neither entry wins. It is a real ethical and tactical blunder for a child who lectures everyone else on doing the right thing.
• Right about the skeleton, wrong about her evidenceLisa the Skeptic, Season 9Lisa's instinct about the angel is sound, but her investigation depends on someone else. The scientist she trusts, Stephen Jay Gould, later admits he never tested the sample. She also does not foresee the mall's stunt and cannot persuade anyone in time. Her scepticism is admirable, but a stronger thinker would have secured the evidence herself.

Canon says 159, which at face value is nearly four standard deviations above the mean. The screen evidence supports about 140. Lisa scores high on knowledge and on principled deduction, moderately on insight, and low on invention, since she rarely builds anything new. Her errors are emotional and social rather than intellectual, but they recur. We also age-normed her at eight, where written-in maturity is easy to over-reward. The gap between 140 and 159 is the gap between what the show says about her and what it shows her doing.

IQ estimates for fictional characters are fan analysis: an argument from what the story shows, not a measurement. Read the full method and the standards we hold every profile to.

Fans argue over whether Lisa's canon 159 makes her the smartest Simpson, and the show itself put Maggie ahead of her in Smart & Smarter, which most viewers read as a gag. The bigger dispute is whether Lisa is a real genius or simply the only person in Springfield who reads. The Mensa episode nudges towards the first, and her habit of being certain rather than correct nudges towards the second. We settle on gifted: well above the Springfield average, below a true prodigy, with a discount for the show's own inflation.

• Hermione Granger IQ: 147The brightest witch, on paper and in practice
• Stewie Griffin IQ: 150Builds time machines, fails at toilets
• Sheldon Cooper IQ: 155Real physicist, fragile ego
• Spencer Reid IQ: 152Memory and math in the field