When Mariah Carey's “All I Want for Christmas Is You” hit theaters 30 years ago on October 29, 1994, her ascension to the throne of Queen of Christmas began.

Three decades later, the 55-year-old pop superstar is everyone's favorite holiday diva.

“It’s the gift that keeps on giving — to her fans and to Mariah,” Gary Trust, managing director of charts and operations at Billboard, told The Post.

“It's No. 1 on Billboard's Best Christmas Songs of All Time chart. Of all the holiday songs ever released, this is the greatest. The chart reflects this.”

The first single from Carey's “Merry Christmas” album – which she co-wrote and produced with Walter Afanasieff – took the octave-hopping singer to historic heights.

“It helped make Mariah the first artist to be No. 1 on the Hot 100 in four decades: the '90s, '00s, '10s and '20s,” Trust said.

But the seasonal standard has had a long, slow rise to the top of the charts.

“His history on the charts is as convoluted as Christmas lights when you hang them on a tree,” Trust said. “Part of it is card manipulation. When the single came out in 1994, it was sent to radio, but you couldn't buy it individually in stores. You could only buy it on the “Merry Christmas” album.

“And back then,” he explained, “the Hot 100 rules were that to be on the Hot 100 you had to be a physically available single.”

But the streaming era propelled “All I Want for Christmas Is You” to the top of the charts in 2019 – where, like Santa Claus, it has returned every year since.

“There’s just something magical about it that really elevates it above all the other Christmas songs this season,” Trust said. “It won’t go away.”

Here we break down some of the significant numbers behind the holiday classic.

1 — Carey earns at least 1 cent every time the song is played. And when the song is repeated around the world, those pennies add up.

5 – Since hitting No. 1 for the first time in 2019, the holiday giant has topped the charts for five consecutive years. And the streak is likely to continue into 2024.

14 – “All I Want for Christmas Is You” spent 14 weeks at the top of the Billboard Hot 100, tying with Carey's 2005 hit “We Belong Together.” But “One Sweet Day,” her 1995 blockbuster with Boyz II Men, is still ahead – at least for now – and has been at the top of the charts for 16 weeks.

19 — When “All I Want for Christmas Is You” topped the charts for the first time in 2019, it became Carey’s 19th No. 1 song, one spot behind the Beatles’ record of 20.

25 — It took a quarter-century for the song to finally reach No. 1 in 2019, when it became Carey's first chart-topper since 2008's “Touch My Body.”

26 — The Tinsel Melody spreads Christmas cheer around the world and has reached number 1 in 26 countries.

61 — It was 61 years between “All I Want for Christmas Is You” reaching No. 1 in 2019 and the previous hit “The Chipmunk Song (Christmas Don't Be Late)” in 1958, which topped the holiday charts.

93 – Fourteen weeks at No. 1 for “All I Want for Christmas Is You” pushed Carey’s record to 93, putting it at the top of the Billboard Hot 100.

23,700,000 — On Christmas 2023, the song blew up Spotify with 23.7 million streams. But Taylor Swift broke Carey's single-day record with 25.2 million streams in April with “Fortnight.”

60,000,000 – Through streaming alone, Carey has earned more than $60 million from the song, not even including more money from album sales, downloads, licenses and other types of royalties.

1,832,654,277 — Entering its 31st holiday season, the song reaches nearly 2 billion streams on Spotify.