Karl Stefanovic turns 50: Today host surprised on his birthday

He's barely stepped off the plane from covering the Olympics in Paris, but the celebrations aren't quite done for our boy Karl.

The Today host is celebrating the big 5-0 today and his co-hosts weren't about to let him get away before making a big fuss for his birthday.

"We love you so much and to celebrate this huge occasion, we got to take a look back at some of the memorable moments from the past five decades," Sarah Abo teased before airing a special video of some of Karl's biggest highlights.

Subscribe to the Today newsletter here. (Nine)Karl's mum Jenny (L) surprised him with a visit to the studio. (Today)

READ MORE: Karl shares cute video of his little Olympian, Harper

And a walk down memory lane wasn't all that was in store for the Nine legend, with none other than his mum, Jenny making the trip down to Sydney from her home in Yorkey's Knob.

"I'm so sorry, my hands are sweaty but nice to see you, mummy," an emotional Karl said before giving his mum a big hug.

And while Karl was squirming a little having all this attention heaped on him, his mum had some beautiful words to share about her eldest son.

"It's great to be here, you've been a great son, when you remember to actually ring your mum," she said.

"And you've been a great brother to your siblings and you've had a great profession which has been terrific, you've picked something you love to do and you've got yourself up at 3am every morning for 20 years, who would do that if they didn't love it?"

The Today team wishes Karl a very happy 50th birthday. (Today)

READ MORE: Karl's sweet gesture after Olympian's raw interview

Karl's sister-in-law, Today Extra host, Sylvia Jeffreys seconded Jenny's well wishes, telling Karl he is "such a treasure" to know.

"You're such a beautiful man and you're a beautiful friend and a beautiful brother and all of us as your colleagues as well, have the rare privilege of seeing the way you can really connect and bring the best out in people, not just the people you interview on the television every day, but the people you work with every day," she said.

"You bring out the best and you show us all how to commit and be really excellent, you're just a wonderful person, you drive us mad and you've made me do things I deeply regret, but we love you with all our hearts."

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