Tiffani Thiessen has left fans shocked after they discovered her age after the actress marked a milestone birthday.
Best known for starring as Kelly Kapowski in Saved By The Bell, Tiffani has been a fan-favorite for decades.
She made her debut on the show in 1989 and remained in the cast until 1993, before joining Beverly Hills, 90210 in 1994 as Valerie Malone.
Tiffani took to Instagram to mark her birthday on January 23, sharing a sultry snap of her with tousled hair and wrapped up in nothing but a bedsheet as she joked she was "over the hill" - but fans couldn't believe her real age as she added: "This is 50."
Her comments were immediately flooded, with Sarah Michelle Gellar writing: "Looks pretty [fire] to me."
Others added: "Happy Birthday! It’s pronounced 40:10 and you look 25!" and: "Happy Birthday - Clearly 50 is the new 32!"
Many fans were in disbelief that she was really 50, writing: "No way you are 50 more like in your 40’s", and: "Forever 29! Happiest of birthdays to you!"
Others commented: "Happy Birthday, Tiffani! You make 50 look like 20," "You are Benjamin Buttoning, happy birthday friend!" and: "Happy 25th birthday," while one added: "You look like you're still 30!"
RuPaul's Drag Race star Willam commented: "happy birthday from a random fan that doesn’t like to comment on people’s looks but also cannot believe you’re not in your 30’s. loved your latest cook book."
Many fans also commended her, writing: "You’ve set the bar very high," "I have a strong suspicion I will not look like that when I turn 50," and: "Wow, I hope I look half as good as u at 50."
Tiffani previously opened up about her desire to age naturally, telling Page Six Style in September that she's never had any work done to her face and probably never will.
She explained: "I like my laugh lines. And I call them laugh lines and happy lines because that’s what they are, you know? And I also cried a lot, too. So they probably were created for that, too. But that’s life. And I earned them."
Now that the 90s icon is a mother to her daughter Harper, 13, and son Holt, eight, with her husband Brady Smith, she wants to "lead by example" so her daughter learns the importance of self-love and not bowing to the pressure of society's beauty standards.
She explained: "I have a teenage daughter, I don’t want her to see that I’m scared [about] turning 50 and that I need to change my face or anything."
Tiffani also spoke about her outlook on aging during an appearance on The Jennifer Hudson Show last year, where she revealed she was more focused on her health rather than her appearance.
She told the host: "Right now I’m really trying to be good [about my health] — not that I haven’t been in the past, because health has always been very important — and I mean body health and mental health.
"But I think in my 40s, my time was really for my children. We give so much to our kids, my child was giving so much to my child, you know, that kind of stuff.
"And now since they’re kids are older, they don’t need me so much as when they were little, it’s a little more me time. It’s about me."
Happy birthday Tiffani!