What is Light Yagami’s IQ?
Top of the national rankings, in a story that never gives a score.
Death Note never assigns Light Yagami an IQ, and the figures circulating online are fan estimates. What the story does give is unusually concrete for fiction: a national examination ranking, and a two-year deduction contest with an opponent of stated equal standing.
Light Yagami’s estimated IQ
- Introduced as the top-scoring student in Japan on the national mock examinations — the story’s own measurement, and the only quantified statement it makes about him.
- Enters To-Oh University joint-first with L, the two of them delivering the freshman address together. The tie is written deliberately: it establishes the antagonists as matched.
- Sustains a two-year deception against a task force with his own father on it, while under direct surveillance for part of that period.
- The central contest with L is conducted almost entirely by inference from constrained information — deducing rules, testing them at low cost, and reasoning about what the opponent can and cannot know.
Every fictional estimate has the same defect: the character is only as clever as the plot lets him be, and his opponents only as slow. Light wins his early rounds partly because the narrative grants him a supernatural instrument with rules that happen to reward exactly his strengths. Read this range as a rating of the portrayal, not of a person.
- First appearance
- Death Note chapter 1, December 2003
- Created by
- Tsugumi Ohba (writer), Takeshi Obata (artist)
- In-story rank
- First nationally on the mock examinations
- University
- To-Oh, entering joint-first with L
- Canonical IQ
- None given anywhere in the source material
What an IQ of 170–190 actually means
Set the claim aside for a moment. If someone genuinely scored in this range, here is what that would represent.
Average is 100 by construction, and about two-thirds of people fall between 85 and 115. Take the test to place your own score on this scale.
| Score range | Classification | Share of people | What it indicates |
|---|---|---|---|
| 85 – 114 | Average | ~68% | The range most people fall into. |
| 115 – 129 | Above average | ~13.6% | Roughly one person in seven. |
| 130 – 144 | Gifted | ~2% | The threshold most high-IQ societies use. |
| Above 144 | Highly gifted | ~0.1% | Figures above this range are extrapolated from the curve rather than measured. |
Percentages are approximate and describe a normal distribution. The same number means different things on tests with different standard deviations.
Thirty questions gives you a measured position on this exact scale — your score, your percentile and the ability breakdown behind it.
Find out in 30 minutes →Who Light Yagami is
Death Note was written by Tsugumi Ohba and illustrated by Takeshi Obata, and serialised in Weekly Shōnen Jump from December 2003 to May 2006, running to twelve collected volumes.
Light Yagami is a Japanese high-school student, top of the national rankings and the son of a police superintendent, who finds a notebook that kills anyone whose name is written in it. He begins executing criminals, is designated “Kira” by the public, and is pursued by a detective known only as L. The two are established early as intellectual equals, and the story is the contest between them.
The series is unusual among manga of its period for being driven almost entirely by reasoning rather than physical conflict — long sequences of rule-deduction, misdirection and inference about what the opponent knows. That structure is why the character turns up in intelligence discussions at all.
By Elora Mercer, Celebrity Research WriterFigures checked by Leon Falkner, Data & Research AnalystReviewed by Aarav Vardhan, Editor-in-Chief · Last reviewed August 2026
Light Yagami: the documented record
The estimate above rests on this record. Every entry here is a matter of public fact, which is more than can be said for the number itself.
- 2003Death Note begins serialisation in Weekly Shōnen Jump.
- 2004The task force investigation and the direct contest with L develop.
- 2006Serialisation ends after twelve volumes; the anime adaptation begins.
- 2007The anime adaptation concludes after 37 episodes.
Where the 165–230 figure came from
Following a claim back to its first appearance is the part almost nobody does — and it is what most people are actually asking.
Fictional profiles on this site are ratings of a portrayal, and the portrayal here is unusually specific. Most fictional geniuses are asserted to be brilliant; Light is given a measurement the story then uses. He is the top-ranked student nationally, he ties L at the university entrance, and the plot is built out of what those rankings imply.
The placement below the Holmes brothers is deliberate. Sherlock and Mycroft are written as performing feats of observation and inference that have no examination equivalent — reconstructing a stranger’s history from a hat, holding the entire machinery of a government in one head. Light’s demonstrated excellence is academic and strategic rather than perceptual, and academic excellence, even at national rank, describes a narrower thing.
He also sits below Moriarty, and for a reason that is arguable rather than obvious. Moriarty is credited in the stories with a treatise on the binomial theorem written at twenty-one and a European chair — original mathematics, in other words. Light’s record is dominance at examinations, which tests the retrieval and application of known material. Producing new mathematics and topping a national examination are not the same achievement, and the ranking here reflects that distinction rather than any judgement about who would win a confrontation.
How we read a number →The source text. Establishes the national examination ranking and the To-Oh tie with L. Contains no IQ figure for any character.
Follows the manga closely on the points relevant here. Also assigns no numerical intelligence score.
Neither the manga, the anime, nor the official supplementary material assigns Light Yagami an IQ score. The absence is the finding.
Source URLs and first-appearance date pending audit.
No canonical origin exists. Several pages present these as official; none cites a volume, chapter or interview.
Placed below Sherlock, Mycroft and Moriarty on the reasoning set out above. Fictional rankings on this site compare portrayals, not characters in a hypothetical contest.
The sources behind our estimate
The figures that circulate for Light Yagami, what we were able to confirm, and where the two diverge.
Figures between 165 and 230 circulate on fan wikis and IQ aggregator pages, usually stated flatly and sometimes attributed to the author. Some pages assert a specific canonical number.
No IQ score for Light Yagami appears in the manga, the anime, or the official supplementary material. The oft-cited numbers are fan estimates that acquired authority by repetition. The character’s only quantified attribute in canon is his examination ranking, which is a measure of tested academic performance within the story — not an intelligence quotient.
A sixty-five point spread on a character whose source text gives no number at all. This is the same failure documented across the real people on this site, reproduced for someone who does not exist.
Want a number that does hold up? Every figure on this page is somebody’s claim. Take the 30-question test and get a percentile you can check rather than a figure you have to trust.
Light Yagami — frequently asked
What is Light Yagami’s IQ?
No figure is given anywhere in Death Note — not in the manga, the anime, or the official supplementary material. The numbers online are fan estimates. Our 170–190 range is a rating of the portrayal.
Is Light Yagami’s IQ 230?
No. That figure has no canonical source. It appears on fan wikis and aggregator pages, sometimes presented as official, but no volume, chapter or interview is ever cited.
Is Light Yagami smarter than L?
The story deliberately ties them — they enter To-Oh University joint-first and share the freshman address. The tie is a writing decision establishing them as matched, so the source text declines to separate them.
How smart is Light Yagami compared to Sherlock Holmes?
We place him below both Holmes brothers and below Moriarty. Light’s demonstrated excellence is academic and strategic; the Holmes characters are written performing perceptual and inferential feats with no examination equivalent.
What was Light Yagami’s exam score?
The story states he ranked first nationally on the mock examinations and entered To-Oh University joint-top with L. It gives rankings rather than raw scores.
Why does a fictional character have an IQ estimate at all?
Because the question is heavily searched and the answers online are invented. This page rates the portrayal against the other fictional profiles here, and says plainly that the source material assigns no number.
How does my IQ compare with Light Yagami?
You can find out in about fifteen minutes. The IQ Metrics assessment is 30 questions, scored on the same 100-mean scale used throughout this page, so your result and the estimate above are at least expressed in the same units — one measured, one inferred. Once you have a number, the leaderboard shows where it would sit, and how we score and norm it explains the benchmarking.
Where does this estimate come from?
From the documented record rather than a test — the method is named above and set out in full under how we read a number. Compare it against the other fictional profiles, starting with Sherlock Holmes.
- Take the 30-question IQ test — get a measured score and percentile of your own
- Average IQ by country — how the scale behaves across populations
- How IQ Metrics scores its assessment — the method behind our own number
- More on how IQ testing works — reliability, error and what a score can and cannot say
- More fictional profiles — same field, same method
More fictional
Photograph of a cosplayer as Doctor Doom by Super Festivals (July 2013), CC BY 2.0. Doctor Doom is a character created by Stan Lee and Jack Kirby for Marvel Comics. Cropped and with background removed for the portrait above. · Photograph of actor Mark Ruffalo by Gage Skidmore (San Diego Comic-Con, July 22, 2017), CC BY-SA 2.0. Bruce Banner is a character created by Stan Lee and Jack Kirby for Marvel Comics, played by Ruffalo in the Marvel Cinematic Universe films. Cropped and with background removed for the portrait above. · Illustration by Sidney Paget (1890s), public domain.
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