A feline in the US has broken the Guinness world record for world's longest domestic cat.

The Reno Gazette-Journal reports that a five-year-old Maine Coon named Stewie was certified as the new record holder after measuring 123.2cm from the tip of his nose to the tip of his tail bone.

Robin Henderson stretches out her Maine Coon cat Stewie, who has just claimed the record as the world's longest cat. Credit:AP

That's a little more than 1.2 metres long.

The record was previously held by another Maine Coon that measured 121.9cm.

Stewie's owners, Robin Hendrickson and Erik Brandsness, say they decided to try for the record after hearing countless people say they were amazed by Stewie's length.

Mr Hendrickson said Maine Coons were known as "the gentle giants" of the cat world.