Simone Giertz started with a punchline on YouTube. Now, she’s figuring out what to build next.

Simone Giertz began her YouTube career building inventions you would never use.

It’s an idea constructed around a punchline. There’s the helmet that brushes your teeth, the robot that fails to serve you breakfast, the hovering drone that cuts your hair. Giertz collapsed those scenes into GIFs for people to share across the many tubes of the Internet; like some primitive episode of the Jetsons.

And, the idea worked. The Swedish inventor, 28, has more than 1 million subscribers on YouTube. She has been on late-night shows with her inventions and gave a Ted Talk about the concept behind her channel.

YouTube can be an unforgiving platform — a black box of sorts — and when creators build a following, they’re then faced with figuring out if they can ever break from the proven format that made their careers. You can get pigeonholed — wedded to the concept your audience expects without any room for growth.

And for a while, that was dysfunctional robots, Giertz told The Post. “What happens when it’s not funny anymore and when I don’t enjoy it anymore? And, that’s like a really scary question.”

Giertz started posting these imperfect robots in 2015; Her YouTube channel now has 1.5 million subscribers and over 6,000 fans support her work through Patreon, a place where fans can donate to creators they admire.

Blase Zinck, 22, is one of those supporters, and he said Giertz’s videos inspire him to think of creative inventions for his daily life — like building a way to keep his cats from ripping up toilet paper.

Her videos put “me in a mood where I just want to do everything,” Zinck added. “It makes me motivated.”

Over time, Giertz said she started to expand past that original concept, but she was concerned with whether her fans would stay.

“What if people leave? What if I don’t like it?,” she said. “You kind of hold on to this format that you’ve built.”

Giertz has been grappling with those question over the past year, in part, because she had to tell the community she built on slapstick comedy that she has a benign brain tumor. Last April, Giertz recorded a sincere message of gratitude, balancing the serious news with a self-described “morbid sense of humor.”

“Sorry that I’m joking about stuff, but it’s really the only way I know how to deal with this, ”she said in that video, which has been played 3.5 million times.

Giertz had surgery last May. She named the tumor Brian and shipped it to Antarctica. But a month ago Giertz learned she’ll need eight weeks of radiation therapy to prevent what’s left of the tumor from growing. She called the news a “bad movie sequel.”

“The campaign for 2018 with surgery was evict Brian. And, now, for 2019 we’re moving on to burn Brian,” Giertz said in a January video.

So, the channel format changed — at least enough to allow Giertz to talk about her health issues over the past year.

“It kind of pushed me to think of YouTube differently,” Giertz said. “In some ways, I’m really happy that I was forced to go through that period of creative soul-searching.”

The new goal for the channel is to be a “journal of personal interest,” whether that interest is robotics, space or an art project.

“If I don’t enjoy it, then, like, what’s the point?,” Giertz said.

Having moved on from failing robots, Giertz talks about having an “incredibly forgiving community.” She has a series on training to be an astronaut. In one video, Giertz locked herself in a bathroom for 48 hours to simulate staying in a confined space ship (that video has 9 million views). The series adds up to be some of her most successful videos, and there’s not a homemade robot in sight. So while Giertz may be concerned about pivoting from what worked, her new style seems to be working, too.

Dianna Cowern, 29, who’s Giertz’s friend and a fellow YouTuber, said Giertz has “an instinctual sense” for what is entertaining and how to pull off those ideas while in front of the camera.

“People were sucked in by the funny concepts and her creative ideas, but they stayed for her,” Cowern said. “And that shows in her recent videos.”

Giertz and a five-person team have also started building inventions to solve problems off YouTube. In November, she announced a Kickstarter for a reward system to build healthy habits everyday (like meditating or reading more) and she wants to build more like it. The goal was to raise $35,000. 2,305 people pledged $593,352 before the campaign closed.

“I want to be an inventor in the real sense,” Giertz said.

YouTube is a platform built for creative people like Giertz. It’s a blank canvas for a generation of self-made Internet stars to appear as a one-man band in front of millions. That’s appealing, but it can become performative. The production cycles are short and there’s a constant need to produce, Giertz said. Inventing off of the platform, like the calendar on Kickstarter, is a way to have variety in a job without any clear next steps.

“There’s this pressure that comes with [YouTube] that’s just relentless,” Giertz said. “We’re coming to a point where people are like ‘How can I have longevity in a career like this?’”

Giertz has big plans — like, have the first television show in space — but she’s navigating a platform where a long career is uncharted territory.

“We’re kind of a guinea pig generation,” Giertz added.

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