Elton John turned 70 over the weekend ... holy crap.

As you might imagine, Sir Elton's birthday party Saturday night drew a HUGE celeb crowd at Red Studios Hollywood, as well as some kick-ass performances.

HAPPY BIRTHDAY TO YOU
TMZ.com

Stevie Wonder played ... so did Lady Gaga. Meanwhile the crowd was full of stars like Katy Perry, Neil Patrick Harris, Rob Lowe, Kelly and Sharon Osbourne, James Corden, Jon Hamm, Jennifer Tilly, David Foster, Dakota Johnson, Matthew Morrison and Ryan Phillippe.

Even at 70 ... Elton's still standing ... and playing. 

RINGING IN 70
TMZ.com