The ‘Keeping Up With The Kardashians’ star shared a series of photographs in honour of the milestone.
“Besitos everyone!!!!! #45mil … Last selfie for the night. Thanks again for the instalove (sic)”
It is not the first time the 34-year-old television personality stripped down for a selfie to celebrate her followers on the photo-sharing site.
She wrote at the time: “27 mil!!!!! Thank you so much!!!! I love you all!!!!! (sic).”
And Kim isn’t shy of posting a revealing photo despite admitting she found it “tough” losing weight after giving birth to two-year-old daughter North.
She said: “I couldn’t help it, and everyone would say, ‘She can’t stop eating.’ I delivered at 180, and they were like, ‘She’s 210 pounds. She’s getting dumped because she’s too fat’ and all these ridiculous stories.
“It really took a toll after the fact, when I was losing weight. I gained 50 pounds, and it’s tough to get it off. I was dedicated, but also, it changed the way I viewed wanting my picture taken.”