It's a grumpy day. Internet's favourite Grumpy Cat is no more

Internet sensation and meme inspiration, Tardar Sauce aka the Grumpy Cat passed away at the age of seven at her home in Phoenix, Arizona.

In a post on Instagram, the official Grumpy Cat handle posted that the beloved cat died on May 14 after a urinary tract infection.

Grumpy Cat was the internet's favourite cat and her grumpy yet hilarious expression was an inspiration for various memorable memes.

"We are unimaginably heartbroken to announce the loss of our beloved Grumpy Cat," Tabatha Bundesen, Grumpy Cat's owner, said according to CNN.

Grumpy Cat, real name Tardar Sauce, had feline dwarfism. This, her owners said, probably accounted for her distinctive facial features and small size.

She became an internet celebrity in September 2012, when Tabatha's brother Bryan posted photos showing her in all her disgruntled glory on Reddit.

Grumpy Cat became such a cultural phenomenon that she inspired art projects, perfumes, merchandise, Skechers shoes, comics and even a "Grumppuccino" coffee.

At the time of her death, Grumpy Cat had 1.5 million followers on Twitter, 2.4 million on Instagram and 8.5 million on Facebook.