--- title: "How many drops of water are there in the ocean? about 27 septi" description: "about 27 septillion How the figure is estimated, how confident it is, and what makes the scale graspable." url: https://atoneplace.net/how-many/drops-of-water-in-the-ocean/ site: "At One Place" --- # How many drops of water are there in the ocean? **How many drops of water are there in the ocean?: about 27 septillion** There are about a hundred times more drops in the ocean than there are stars in the observable universe. The oceans hold about 1.33 billion cubic kilometres of water, a figure that is known to within a few percent from satellite altimetry and sea-floor bathymetry. A "drop" is not a physical constant, but pharmacy convention fixes it at 20 drops per millilitre, or 0.05 mL. Multiply the two and you get roughly 2.7 × 10^25 drops. Unlike most entries on this page the uncertainty is small, because the ocean's volume is genuinely well measured — the wobble is all in what counts as a drop. ## How the figure is arrived at 1.33 billion km³ × 10^15 mL per km³ = 1.33 × 10^24 mL. At 20 drops per mL that is 2.66 × 10^25 drops. If you prefer a "drop" of 0.1 mL — closer to what falls off a tap — halve the answer. ## How confident it is - **Low estimate:** 26,000,000,000,000,000,000,000,000 - **High estimate:** 28,000,000,000,000,000,000,000,000 - **Spread:** 1.1× between the bounds ## Other living things and the natural world counts - [How many people are there in the world?](https://atoneplace.net/how-many/people-alive-right-now/) — about 8.2 billion - [How many grains of sand are there on Earth?](https://atoneplace.net/how-many/grains-of-sand-on-earth/) — roughly 7.5 quintillion on the world's beaches - [How many ants are there in the world?](https://atoneplace.net/how-many/ants-on-earth/) — about 20 quadrillion - [How many trees are there in the world?](https://atoneplace.net/how-many/trees-on-earth/) — about 3 trillion - [How many insects are there?](https://atoneplace.net/how-many/insects-on-earth/) — about 10 quintillion - [How many species are there?](https://atoneplace.net/how-many/species-on-earth/) — about 8.7 million - [How many people have ever lived?](https://atoneplace.net/how-many/people-who-have-ever-lived/) — about 117 billion - [How many fish are there in the sea?](https://atoneplace.net/how-many/fish-in-the-sea/) — somewhere between 3 trillion and 100 trillion — nobody knows - [How many species are endangered?](https://atoneplace.net/how-many/endangered-species/) — more than 45,000 assessed as threatened - [How many bees are there in the world?](https://atoneplace.net/how-many/bees-in-the-world/) — roughly 2 trillion managed honey bees - [How many birds are there in the world?](https://atoneplace.net/how-many/birds-in-the-world/) — about 50 billion wild birds - [How many bacteria are there on Earth?](https://atoneplace.net/how-many/bacteria-on-earth/) — about 5 nonillion - [How many earthquakes are there each year?](https://atoneplace.net/how-many/earthquakes-a-year/) — about 20,000 located a year — around 55 a day - [How many chickens are there in the world?](https://atoneplace.net/how-many/chickens-in-the-world/) — about 26 billion alive at any moment ## Common questions ### How many drops of water are there in the ocean? about 27 septillion ### How is that estimated? 1.33 billion km³ × 10^15 mL per km³ = 1.33 × 10^24 mL. At 20 drops per mL that is 2.66 × 10^25 drops. If you prefer a "drop" of 0.1 mL — closer to what falls off a tap — halve the answer. ## Related pages - [How many people are there in the world?](https://atoneplace.net/how-many/people-alive-right-now/) - [How many grains of sand are there on Earth?](https://atoneplace.net/how-many/grains-of-sand-on-earth/) - [How many ants are there in the world?](https://atoneplace.net/how-many/ants-on-earth/) - [How many trees are there in the world?](https://atoneplace.net/how-many/trees-on-earth/) - [How many insects are there?](https://atoneplace.net/how-many/insects-on-earth/) - [How many species are there?](https://atoneplace.net/how-many/species-on-earth/) - [How many people have ever lived?](https://atoneplace.net/how-many/people-who-have-ever-lived/) - [How many fish are there in the sea?](https://atoneplace.net/how-many/fish-in-the-sea/) - [How many stars are there in the universe?](https://atoneplace.net/how-many/stars-in-the-universe/) - [How many countries are there in the world?](https://atoneplace.net/how-many/countries/) - [How many bones are in the human body?](https://atoneplace.net/how-many/bones-in-the-human-body/) - [How many stars are there in the Milky Way?](https://atoneplace.net/how-many/stars-in-the-milky-way/) - [How many atoms are there in the universe?](https://atoneplace.net/how-many/atoms-in-the-universe/) - [How many galaxies are there?](https://atoneplace.net/how-many/galaxies-in-the-universe/) ## Sources - Calculated on this page — At One Place (/about/)