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Head-to-Head Comparison

Max Planck vs William James Sidis

Max Planck (IQ 190) vs William James Sidis (IQ 250). Side-by-side comparison of intellect, achievements, era and cultural impact.

Max Planck
1858–1947 · DE
190
Estimated IQ
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William James Sidis
1898–1944 · US
250
Estimated IQ
Read full biography →
Born18581898
Died19471944
CountryDEUS
Estimated IQ 190 250
Best known forOn the Second Principles of Mechanical Heat Theory (1879)The Animate And The Inanimate

Who had the higher IQ?

By the most cited estimates, William James Sidis tops this matchup with an estimated IQ of 250, a 60-point margin over Max Planck (190). IQ estimates for historical figures are reconstructions, not test results — they sit on top of biographical evidence, productivity, and the difficulty of the problems each person solved. Treat the number as a directional signal, not a verdict.

Achievements compared

Max Planck is best known for: On the Second Principles of Mechanical Heat Theory (1879) William James Sidis is best known for: The Animate And The Inanimate

Recognition. Max Planck: Nobel Prize in Physics (1918) • Foreign Associate of the National Academy of Sciences (1926) • Lorentz Medal (1927) • Copley Medal (1929) • Max Planck Medal (1929) • Goethe Prize (1945). William James Sidis: —.

Different eras, different boards

The two were born roughly 40 years apart (1858 vs 1898), which matters: scientific tools, available knowledge, and intellectual culture compound. Comparing minds across eras is comparing players on different boards.

The verdict

So who was greater? The honest answer: they're not strictly comparable. By raw IQ proxy, William James Sidis edges out. By measurable, lasting influence in their respective field, both are anchors of the human record. If you have to pick one to bet civilization on, pick the one working on the problem you care about.

Frequently Asked

Who had the higher IQ, Max Planck or William James Sidis?
Estimated IQs are 190 for Max Planck and 250 for William James Sidis. William James Sidis rates higher by 60 points. Historical IQ figures are reconstructions, not measured scores.
What is Max Planck most famous for?
On the Second Principles of Mechanical Heat Theory (1879)
What is William James Sidis most famous for?
The Animate And The Inanimate
Did Max Planck and William James Sidis ever meet?
They were contemporaries, though there is no documented direct meeting in our sources.

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