The actress played Monica Geller on the beloved sitcom, which remains one of the most popular shows on TV despite finishing in 2004.
Cox appeared on a stripped back version of Jimmy Kimmel’s late-night show, which is off-air due to the pandemic, to discuss how she is keeping occupied amid the shutdown in California.
Appearing via video link from her home, Cox revealed she bought all 10 seasons of Friends on Amazon Prime after it was taken off Netflix in anticipation of the HBO Max launch. She is now busy making her way through the 236 episodes.
“I decided during this time, people love the show so much, I decided to binge watch Friends. I just started season one – it’s really good!” she said.
However, Cox, 55, stunned Kimmel when admitting her memories of being on Friends were foggy at best.
“I don’t remember even being on the show, I have such a bad memory. I remember obviously loving everybody there and having fun and I remember certain times of my life I was there but I don’t remember episodes,” she said.
To test how bad her knowledge of Friends was, Kimmel had Cox go head-to-head with his cousin, a huge fan of the show, in a quiz.
Despite the questions all being Monica related, Cox was beaten 5-0.
Questions to which she did not know the answer included the identity of Monica’s first kiss and who peed on her leg in season four episode The One With The Jellyfish.
Cox used her appearance on Kimmel’s stream to ask viewers to make a donation to the Meals On Wheels charity.
She also confirmed filming for the long-awaited Friends reunion special has been postponed due to the coronavirus crisis.
Cox said she and former co-stars Jennifer Aniston, Lisa Kudrow, Matthew Perry, Matt LeBlanc and David Schwimmer were supposed to shoot the programme on Monday and Tuesday, but it has been pushed back.
The Friends reunion special is still slated to be available at the launch of the HBO Max streaming service in May.
Additional reporting by Press Association