Hello how may I help you? Who is the worlds tallest person? Do you mean the world's tallest living person or the world's tallest person ever? living The world's tallest living person is Sultan Kosen How tall is he? He is measured at 8 foot, 3 inches tall Who was the tallest person ever? The tallest person ever was Robert Wadlow and his height? 8 foot, 11 inches, almost 9 feet tall! Thanks bot.