Stephen Hawking's IQ is not publicly known. While he was a renowned physicist and a brilliant mind, he never publicly disclosed his IQ score.
It's important to remember that IQ tests are just one measure of intelligence, and they don't capture the full spectrum of human abilities. Stephen Hawking's contributions to science, his resilience in the face of adversity, and his ability to communicate complex ideas to a wide audience are all testaments to his remarkable intellect.