The length of a bacterium is about 20 times the characteristic size of a virus. Selected basis: a representative value for Virus; an example for Bacterium; approximate values.
Both rulers start at the same zero and share one linear scale. Artwork keeps its original proportions.
100 nm - Characteristic size; representative.
A virus is an infectious particle containing genetic material inside a protein coat, sometimes with an outer envelope. It reproduces only inside host cells.
A chosen 100 nm viral particle, including the approximate envelope. Viruses vary greatly.
University of Utah — Cell size and scale2 µm - Length; example.
A bacterium is a single-celled microorganism without a membrane-bound nucleus. Different bacterial species have very different forms and sizes.
A 2 µm long illustrative bacterium. Species and growth conditions vary.
Defined examples — our methodology
There’s always another scale
MicroscopicVirus100 nmA virus is an infectious particle containing genetic material inside a protein coat, sometimes with an outer envelope.
MicroscopicBacterium2 µmA bacterium is a single-celled microorganism without a membrane-bound nucleus.
Fundamental physicsProton1.682 fmA proton is a positively charged particle found in the nucleus of atoms, made up of quarks.
MicroscopicCell10 µmA cell is the basic structural unit of living organisms.
PeopleHair70 µmA hair is a slender strand of protein that grows from the skin of humans and other mammals.A closer look
Side by side
Illustrative artwork · not to scale
Illustrative artwork · not to scale
Illustrative artwork · not to scale
Illustrative artwork · not to scaleGot a good eye for scale?