How many grains of sand are there on earth?

They said, if you assume a grain of sand has an average size and you calculate how many grains are in a teaspoon and then multiply by all the beaches and deserts in the world, the Earth has roughly (and we're speaking very roughly here) 7.5 x 1018 grains of sand, or seven quintillion, five hundred quadrillion grains. read more

They said, if you assume a grain of sand has an average size and you calculate how many grains are in a teaspoon and then multiply by all the beaches and deserts in the world, the Earth has roughly (and we're speaking very roughly here) 7.5 x 10 18 grains of sand, or seven quintillion, five hundred quadrillion grains. That's a lot of grains. read more

But more likely, there are 5 to 10 times more stars than there are grains of sand on all the world’s beaches. So, there’s your answer, Sheldon. For some “back of the napkin” math we can guess that there are more stars in our Universe than there are grains of sand on all the beaches of Earth. read more