The stars revealed their natural skin in the hours before the 95th Academy Awards is due to kick off in LA tonight.
Kardashian, 42, who is believed to be attending the Elton John AIDS Foundation Academy Award Party after the ceremony, underwent a "resurfacing" treatment.
The businesswoman visited cosmetic surgeon Dr Simon Ourian who revealed on his Instagram that he had used a procedure designed to "treat sun damage, tighten the skin, and shrink pores".
Dr Ourian added in the caption to a video of a bare-faced Kardashian that the "Coolaser" technology costs between $2,900 (£2,399) and $5,900 (£4,882) per go.
The star, who shared the same clip to her own social media, revealed that her skin felt "numb" but that she was "relaxed".
Meanwhile, Berry appeared to indicate that she was letting her skin breathe ahead of glam for the Academy Awards red carpet.
In a post on Instagram, the actress, 56, could be seen smiling as she unveiled her make-up-free complexion.
Captioning the video, the star wrote: "Guess who’s going to the ball tomorrow."
The clip received more than 129,000 'likes', with fellow actress Julianne Moore commenting with a 'flame' emoji.
Kate Bosworth, Florence Pugh and Kate Hudson were among the other big Hollywood names to also give fans an insight into beauty preparations on their Instagram Stories.
As usual, the ceremony took place at the Dolby Theatre in Hollywood on Sunday evening and this year was hosted by Jimmy Kimmel.
Watch: British and Irish talent gear up for 95th Academy Awards in LA