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Beethoven’s 165 is one of the few figures on this site with a real document behind it — Catharine Cox’s 1926 study. That document is also the reason to treat the number carefully: it is an estimate of a childhood nobody recorded well.
The Cox estimate is not a measurement. It is a rating assigned by readers of biographical material, and its own authors flagged that figures for subjects with thin childhood records are systematically depressed. Beethoven’s early record is thinner than Mozart’s, which is one reason to read 165 as a ceiling rather than a centre.
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 →Ludwig van Beethoven was baptised in Bonn on 17 December 1770. His father, a court singer, taught him and pushed him hard toward a prodigy career; he was appointed assistant court organist as a teenager and had work in print before he left for Vienna.
He settled in Vienna in 1792, studying briefly with Haydn, and made his early reputation as a pianist and improviser rather than as a composer. His hearing began to fail around 1798, when he was in his late twenties. The Heiligenstadt Testament of 1802 records what that meant to him.
He kept composing for twenty-five more years, through and past total deafness — the late quartets, the Missa solemnis he holds in the Stieler portrait above, and the Ninth Symphony, premiered in 1824 when he could not hear it. He died in Vienna in 1827.
By Elora Mercer, Celebrity Research WriterFigures checked by Leon Falkner, Data & Research AnalystThe 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.
Following a claim back to its first appearance is the part almost nobody does — and it is what most people are actually asking.
This is the rare page where the audit ends well. The number is traceable, the study is named, and the method is written down. Cox’s The Early Mental Traits of Three Hundred Geniuses (1926) is the second volume of Terman’s Genetic Studies of Genius, and the figures reproduced across the internet come from column 25 of its Table 12A.
The method deserves stating plainly, because knowing it changes how much weight the number can carry. Cox’s raters read biographies and inferred what a child must have been capable of. A subject with a well-documented childhood — letters, school records, prodigy anecdotes — scores higher than an equally able subject whose early life went unrecorded. Cox knew this and corrected for it. The correction is an adjustment, not a measurement.
Beethoven and Mozart landing on the same 165 is therefore less a finding about the two men than a fact about two similar childhood dossiers. Both were performing publicly as children under a musician father; both left early evidence a rater could work from. The identical figure should be read as the study being consistent, not as a verdict that the two were equally able. Compare Voltaire at 190 and Goethe at 210 from the same table.
How we read a number →The origin of the 165. Volume II of Terman’s Genetic Studies of Genius; figures taken from column 25, “Corrected IQ estimate” (AII), of Table 12A, based on evidence to age twenty-six.
A letter to his brothers, never sent, describing his deafness. A first-person document of the period when he understood the hearing loss was permanent.
Visitors wrote their side of conversations down for him once he could no longer hear. Roughly 139 survive — an unusually direct record of an adult subject’s daily exchanges.
Beethoven died in 1827. Intelligence testing began with Binet in 1905. No test of any kind exists or could exist.
Several sites present a downward-adjusted Beethoven figure near 135–150. These are recalculations of Cox, not independent evidence, and should not be read as a second source.
The figures that circulate for Ludwig van Beethoven, what we were able to confirm, and where the two diverge.
165 is quoted almost universally, and almost always without saying where it comes from — which is a pity, because unlike most figures on this site, it has an actual source.
The 165 is genuine Cox data, and it is still not an IQ score. Cox’s team read biographies and assigned ratings on the Stanford–Binet scale using evidence up to age twenty-six, then corrected for regression to the mean. Beethoven sat no test; he died in 1827, eighty years before one existed.
The lower figures come from Cox’s uncorrected column and from later commentators applying a Flynn adjustment. Same study, different arithmetic — which is a better class of disagreement than most pages here document.
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.
No test exists — he died in 1827, before intelligence testing was invented. The 165 that circulates is a historiometric estimate from Catharine Cox’s 1926 study, not a measured score. Our range is 150–165.
Column 25 of Table 12A in Cox’s The Early Mental Traits of Three Hundred Geniuses (1926). It is a corrected rating assigned by researchers reading biographical evidence up to age twenty-six.
Cox gives both men 165, which reflects two similarly well-documented musical childhoods rather than a finding that they were equally able. The study cannot separate them, and neither can we.
Yes. His hearing failed from about 1798 and was effectively gone by 1818. The Ninth Symphony, the late quartets and the Missa solemnis all date from after that.
It is a real study with a stated method, which puts it far above the unsourced figures elsewhere on this site. But it rates surviving biographical evidence, so subjects with thin childhood records score lower regardless of ability.
Among the figures profiled here, Goethe at 210 and Voltaire at 190 sit above Beethoven and Mozart, both at 165. The ranking tracks documentary survival as much as ability.
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.
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 musicians profiles, starting with Brian May.
Portrait © Matthew Yohe, CC BY-SA 3.0. The background-removed portrait above is a derivative work and is likewise offered under the same licence. · Portrait © Debbie Rowe / The Royal Society, CC BY-SA 3.0. The background-removed portrait above is a derivative work and is likewise offered under the same licence. · Portrait by Christopher Smith, U.S. Department of Health and Human Services — a work of the U.S. federal government, public domain. Background removed for the portrait above.
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