When Devin Stratton slipped on his backpack to go backcountry skiing last week, he had no idea the apparatus would play a role in saving his life. On the mountainside, it’s usually what’s in the pack that counts — an ice ax, a shovel and other avalanche safety gear. But Stratton learned a valuable lesson that sunny day in the Wasatch Range in Utah.

“It’s not just avalanches you’re worried about,” the 25-year-old fishing instructor said in a phone call on Wednesday.

The concern that day was the unmarked 150-foot cliff that Stratton accidentally skied off.

Stratton captured what he describes as a near-death experience on a GoPro camera his sister gave him two years ago. He said he hardly wears it, but on this particular outing, he gave it a go.

“I’m super glad I did,” he said. “I would never wish for it to happen to anyone, but it’s pretty lucky to have on video.”

Stratton posted an edited version of the video late Tuesday night on his Instagram account and tagged the popular ski blog “Jerry of the Day.” By Wednesday morning, the video had gone viral, landing on websites such as Deadspin and Fox Sports.

While Stratton — who credits two and a half feet of soft snow and his backpack for softening his landing on the icy crust beneath the surface — is enjoying his viral fame, he remembers the experience as one of the most-terrifying moments of his life.

“I immediately thought about my cousin who was [left a] quadrapeligic from a car accident and thought, ‘I’m gonna be paralyzed,’ ” he said Wednesday. “And then when I saw how big the cliff was when I was going over the edge, I thought I was dead for sure.”

“I [prayed] in my head in midair,” Stratton added. “It doesn’t sound like it in the raw footage because I’m cussing. But in my head, I was praying.”

Stratton said when he first hit the ground, it took him a few seconds to realize he was actually alive. He said he then immediately started yelling up to his friend who was skiing behind him to watch out, lest he follow in Stratton’s tracks and fly over the edge, as well.

“I saw him come around and I was relieved that he’s not gonna come land on me and kill us both,” Stratton said of his buddy, who helped him locate a ski he lost in the accident.

“We spent nearly five hours where I landed digging, looking for one of my skis. And every time I looked up at the cliff, I felt sick to my stomach,” he said. “I’m super lucky to be alive, or at least not hurt … Not even a scratch or a bruise.”

Stratton insisted he doesn’t plan to repeat his cliff-jumping adventure, but he also doesn’t plan to cease participating in the sport he’s loved since he was 14. Since last week’s accident, Stratton said he’s hit the slopes three times. And on Wednesday he said he was heading to another Utah resort to ski again. This time, though, he’s planning to be a bit more cautious.

“If I’m unfamiliar with the territory, I’m gonna go slow until I know it really well,” he said.