A selfie and a satellite nerd played key roles in the rescue of a hiker who’d gotten lost deep in the mountains of California earlier this week.

Rene Compean, 46, was hiking in the San Gabriel Mountains in Southern California on Monday when he paused to snap a shot of his feet dangling over a picturesque cliff near the Mount Waterman area, according to the Los Angeles County Sheriff’s Department.

Compean texted the picture to a friend — and then sent a later message saying he was lost and his cellphone was dying.

The pal reported his friend missing around 6 p.m. and turned the photo over to authorities, who blasted out the picture on social media in hopes that someone could help pinpoint Compean’s location.

“The hikers legs (in the picture) look dirty possibly from a burn area on the mountain,” authorities wrote. “If you recognize the area pictured below, please call us.”

Compean had the “location” feature switched off on his phone, meaning officials couldn’t immediately track down where he was.

But they got a break thanks to Benjamin Kuo — and his knack for technology and penchant for tracking wildfires.

“I’ve got a very weird hobby, which is, I love taking a look at photos and figuring out where they’re taken,” said Kuo told NBC Los Angeles.

Kuo figured out coordinates of where Compean possibly was — passing on the crucial bit of information to investigators.

“This was a good clue and it was worth investigation,” Sgt. John Gilbert with LASD’s Crescenta Valley Station told the network. “So that’s when we asked our Air Rescue 5 to go and check out that area and see if they saw anything, lo and behold, we were able to find him.”

Compean was rescued Tuesday afternoon and met the man who saved him.

“I crazy appreciate what you did … I really don’t know if I could make it there another day. It was just so cold,” Compean told Kuo.

Kuo told him he was able to narrow down his location based on the background below his shoes in the photo.

Compean said he believes he got lost due to signposts that may have been burned down in a recent wildfire.