SESKStuff Everyone Should Know
SESK: Stuff Everyone Should Know · sesk.info/home-yard-mouse-pencil-gap

How small a round hole can a mouse squeeze through?

About one-quarter inch, the width of a pencil.

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  1. One-quarter inch ✔
  2. One inch
  3. Three inches

Why: Mice can enter through surprisingly tiny openings. Checking pencil-width gaps helps find possible entry points.

Huh, didn't know that: The CDC recommends looking for gaps both inside and outside a home.

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What kind of music do mice like? Mouse-ic.
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References

Answer: One-quarter inch. Mice can enter through surprisingly tiny openings. Checking pencil-width gaps helps find possible entry points.

  1. Seal Up to Prevent Rodents, CDC www.cdc.gov/healthy-pets/rodent-control/seal-up.html
    Mice can fit through a hole the width of a pencil (1/4 inch or 6 millimeters in diameter).
    Checked 2026-10-11.

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