A mouse can get through a small, 6-7 mm hole (about the diameter of a normal-sized pen) and a rat can get through a 20 mm hole. They can also jump several decimetres at a time.Click to see full answer. Likewise, people ask, can rats fit under doors?Rats and mice can crawl through very small spaces (under doors, into crevices, etc.) and when they can’t fit, then they simply gnaw and chew their way through.Beside above, can a mouse fit through 1/4 inch hole? I specifically remember studying about this- it turns out that mice can easily fit through a 1/4 inch hole- About the sizw of a dime. Rats- a half inch. As many ballpoint pens are slightly different in diameter, it’s hard to say. Either way, that’s a small hole! Accordingly, can rats squeeze through cracks? Rats can enter buildings in numerous ways. Regardless of their size, they can squeeze through small openings in walls where wires and pipes are installed. They can even squeeze through holes or wall cracks that are as small as a dime. But, rats are not all about squeezing through holes – they are also great at digging.How Small gaps can mice get through?Young mice can squeeze through a 5 mm gap, sneaking in to spaces as small as a pencil width. Mice are able to jump up to about 24 cm high, which is quite a feat, considering their average size is between 3 and 10 cm.