Rachel Riley stunned on 8 out of 10 Cats tonight as she flashed the flesh in a skimpy yellow gown.

The 35-year-old beauty took to the Channel 4 show to host the Countdown segment in a silky bright yellow sleeveless dress.

Rachel looked as beautiful as ever as she flashed the flesh in the piece which trailed down to the floor but featured a very daring slit up one leg.

The piece also hung from just one shoulder as the other was left bare, other than a teeny and hardly noticeable strap keeping the math genius' modesty in tact as she changed the letters.

Rachel Riley stunned on 8 out of 10 Cats does Countdown tonight

The blonde bombshell wore her hair down for the occasion and left her locks to fall past her shoulder.

Rachel completed the look with a pair of high-heels and a blue headband around her hair just over her forehead.

For her make-up, she opted for a a pink glossy lip and subtle smokey eye.

Viewers of the show were also loving Rachel's look and took to Twitter to share their thoughts.

Rachel looked beautiful in the yellow gown

One tweeted: "Rachel Riley is smart and beautiful, proper girl crush #CatsCountdown."

A second wrote: "Rachel looks banging tonight," followed by the love-struck emoji.

"Rachel is just so fit," gushed another fan of the star's beauty.

It comes after Rachel was left blushing following a rude anagram during a recent episode of Channel 4's Countdown.

Much to the delight of social media, the anagram the contestants were presented with was "SLEAZYNOB".

Mathematician Rachel was smirking when the word appeared on the board.

Last month, she offered a sultry grin when the word "orgasmed" was revealed after comedian Shappi Khorsandi revealed the eight-letter word.