Hello how may I help you? Can you look up something for me? Yes, I can help. I want to know who the world's tallest person is? Do you mean the tallest living person or the tallest person ever? How about the tallest person that ever lived? Robert Pershing Wadlow is the tallest person that has ever lived. Can you tell me how tall he was? He stood 8'11" tall. That sure is tall. I don't think he could walk in my house very well. Thanks! You're welcome!