Smallest Non Living Organism

Although there is still some debate about what is considered alive and what isnt, most biologists would not classify a virus as a living organism due to the fact that it cannot reproduce or metabolize by itself. A virus, however, can get much smaller than any living organism including the bacterium we just saw. The smallest is the single stranded DNA virus Porcine circovirus you see here. It is only 17 nanometers across.