Microscopic · #995 biggest of 1,014
How big is a bacterium (E. coli)?
2 µm
A bacterium (E. coli) measures 2 µm. That's about 20 viruses lined up end to end.
By the numbers
- That's 2 micrometers (µm) — far too small to see with the naked eye.
- You'd need about 850,000 of them stacked up to reach the height of an average adult.
- Roughly 20 viruses could line up across it.
- Out of all 1,014 things in this collection, it ranks #995 by size.
Size comparison
How bacterium (E. coli) stacks up against things of a similar size. Tap any bar to explore it.
red blood cell
7.5 µm
red blood cell
7.5 µm
chloroplast
5.0 µm
yeast cell
4.0 µm
bacterium (E. coli)
2.0 µm
mitochondrion
1.0 µm
wavelength of red light
7.0e+2 nm
wavelength of blue light
4.5e+2 nm
smallpox virus
3.0e+2 nm
Bars use a logarithmic scale so everything fits — real differences are even more extreme!
Fun fact
It's so small that about 500 of them would fit across a single millimeter.
More in Microscopic
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