Macaulay Culkin has set the internet alight with a cheeky message to millions.

“Hey guys, wanna feel old?” he tweeted on Wednesday (US time).

“I’m 40. You’re welcome.”

Tweet from @IncredibleCulk

Culkin also joked he was heading into a midlife crisis, saying: “I’m thinking of picking up surfing. Do you all have any suggestions?

“Do any of you have Photoshop skills? Can you put my head on a surfer so I can get an idea of how cool I’d look?”

But it’s true, the former child star – most famous for playing Kevin McCallister in the Home Alone films – is ageing just like the rest of us.

Culkin, who was 10 when he first starred as the resourceful Kevin, was born on August 26, 1980. He had a string of other movie hits, including 1991’s My Girl and 1994’s Richie Rich.

But it is Kevin McCallister for whom he remains best known. So much so that he revised the role in a YouTube series in 2018.

In the first episode of :DRYVERS, a worse-for-wear Culkin explains the post-traumatic stress caused by being left alone by his family over the holidays.

Holding a cigarette and sporting long, dirty hair, Culkin, who plays an angry husband filling in for his wife’s hire car company, explains to a passenger why he is rejecting his mother’s phone calls.

All grown up – Macaulay Culkin in December 2019. Photo: Getty

“You think that’s cold?” Culkin asks the passenger, played by series creator and writer Jack Dishel.

“How about this: it’s Christmas time. It’s f—ing Christmas and your whole family goes on vacation and they forget their eight-year-old f—ing son.”

“All by yourself in the house for a week.

“I had to fend off my house from two psychopath home invaders. I was just a kid.

“The cutest eight-year old kid in the f–ing universe.

“I couldn’t even eat a slice of pizza without going to war.”

These days, after dallying in music for a few years, Culkin has returned to acting and making podcasts. He often returns to the role of Kevin – including in a 2018 ad for Google Assistant.