How much does the world poop?
An average human produces about 0.5 kg of poop per day — the exact figure wobbles between 0.3 and 0.8 kg depending on how much fibre you eat, but 0.5 is a fair round number. Now multiply that by every living human.
46 tonnes per second4 million tonnes a dayone Lake Bled a week
The question: How much poop does humanity produce per second?
the result
46 tonnes per second
First the whole day: 8 billion people × 0.5 kg. Then remember how many seconds fit into a single day.
Work it out
- 8 × 10⁹ people × 0.5 kg ≈ 4 billion kg per day — that is 4 million tonnes.
- One day = 24 × 60 × 60 = 86,400 seconds.
- 4,000,000 t ÷ 86,400 ≈ 46 tonnes per second.
- Fun unit: × 60 ≈ 2,800 tonnes per minute ≈ 2,800 m³ — more than one Olympic swimming pool (2,500 m³) every minute.
- Per year: 4 billion kg × 365 ≈ 1.5 billion tonnes — roughly one Lake Bled every six days (see the lake-showering exercise… you've been warned).
About 46 tonnes per second — 4 million tonnes a day, 1.5 billion tonnes a year: an Olympic pool of the stuff every minute, a whole Lake Bled every week.
What it teaches
Dimensional analysis: the same fact becomes believable (0.5 kg a day), absurd (an Olympic pool a minute) and planetary (a lake a week) just by changing the unit. Global numbers only make sense once you choose your scale.