How many bacteria live on a typical smartphone screen?

Science hard Data from 2023

Guess before you scroll — the answer is below

Answer in bacteria per square inch. Shorthand like 9m or 1.2bn works.

The answer

17,000 bacteria per square inch

Roughly 17K.

A typical phone screen carries around 17,000 bacteria per square inch — roughly ten times more than a toilet seat, which is cleaned regularly and rarely pressed against your face.

Where this number comes from

Source University of Arizona microbiology research
Figure refers to 2023
Last checked
Unit bacteria per square inch

Numbers move. If this one has drifted from its source, let us know.

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