Ocean Life Quiz
Trenches, reefs, sharks and the biggest fish in the sea. Ten questions about the water that covers most of the world and almost everything living in it.
Play nowSeventy-one per cent of the planet, barely explored.
Ten questions, no timer, no penalty for guessing. Use the number keys 1-4 if you are in a hurry.
We have better maps of Mars than of our own seafloor
The ocean covers about 71% of the planet and most of it has never been directly observed.
The Mariana Trench runs deeper than Everest is tall, and the pressure at the bottom is over a thousand times what you feel at the surface. Life thrives there anyway, around hydrothermal vents that run on chemistry rather than sunlight. Closer to the surface, coral reefs occupy well under one per cent of the ocean floor while supporting roughly a quarter of all marine species.
Scoring: one point per correct answer. 0-3 makes you a Beginner, 4-7 an Explorer and 8-10 a Master. Your best result is kept in this browser, so you can come back and try to beat it.
Frequently asked
How many questions are in the Ocean Life Quiz?
Ten multiple-choice questions with four options each and exactly one correct answer. A full round takes about 4 minutes.
Is the Ocean Life Quiz free to play?
Yes, completely. There is no account, no paywall and no download — the quiz runs entirely in your browser.
How difficult is this quiz?
It is rated Medium. Seventy-one per cent of the planet, barely explored. Every answer is followed by a short explanation, so even a low score is useful preparation for the next attempt.
Is my score saved?
Your best result is stored in your browser with localStorage, so it survives a refresh and is shown at the top of the page next time you visit. Nothing is uploaded anywhere.
Related quizzes
Three more rounds picked to follow this one, starting inside nature.