Not all side hustles require you to fill up your gas tank or form an LLC.

The right virtual gig can help you make extra money from the comfort of your own couch, say side hustle experts. Most options only require a laptop — cozy blankets and college degrees optional — and some can pay up to $270 for only 30 minutes of work.

The average American has about five hours of free time per day, according to the Centers for Disease Control and Prevention — so it helps to know which side hustles are worthy of your time. Gigs like artificial intelligence training and virtual assisting can take longer to start, but they usually pay more than other low-effort side hustles, even if you can only commit one night per week, says Nick Loper, founder of the Side Hustle Nation blog.

"There's a whole world of low-paying survey apps, and you can get paid to play mobile games," Loper says. "For a little bit higher earning power, you're probably going have to fire up your laptop."

Here are four remote side hustles you can start right now:

Online surveys

Some websites and apps will pay you to answer survey questions, typically so they can use or sell the data they collect for customer and market research.

Some, like Swagbucks, allow you to take surveys, play games or participate in cashback shopping, and get paid through gift cards, PayPal or a check. But you don't earn very much money per activity, meaning other options provide a better per-hour rate, says Kathy Kristof, who runs the side hustle review blog SideHusl.

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Kristof's recommendation is research firm Prolific, which pays participants a minimum of $8 per hour to fill out surveys for AI firms and universities, according to its site. But there's currently a waitlist to join, and sites with higher payouts do typically have more rules and barriers.

Research platform Respondent, for example, only allows you to take surveys that need responses from someone in your demographic range or with your level of professional experience. Current listings include a general survey about sexual wellness, which pays $40 for 20 minutes of participation, and a CEO survey about generative AI that pays $270 for 30 minutes.

The average Respondent project pays $75, according to its website.

Virtual tutoring

You can virtually tutor on any subject, from academic classes to music lessons or even social skills. Platforms like Outschool or Wyzant typically allow you to set your own rates, meaning the amount you make can vary depending on your experience and topic expertise.

You might need to take some time to figure out which skills are in-demand during your available hours, and use that knowledge to start building a loyal clientele. Bar exam tutors on Wyzant typically charge between $40 and $90 per hour, and elementary math tutors charge between $30 and $50 per hour, according to the platform.

Wyzant keeps about 25% of each transaction, and Outschool keeps 30%, according to their websites.

Steve Menking, a former equities trader at SMB Capital, found success charging $150 per hour on Wyzant back in 2017 for tutoring in subjects like accounting and calculus, he told CNBC Make It last month.

For extra cash: If you create your own teaching materials, like worksheets or lesson plans, you can sell them on Teachers Pay Teachers, an Etsy-style online marketplace for professional educators.

AI training

AI trainers evaluate the accuracy, precision and effectiveness of chatbot responses. At some tech companies, that's a full-time job — but everyday people can sign up on websites like Remotasks and DataAnnotation Tech to chip in during their free time.

To get onto DataAnnotation Tech's platform, you to take an hour-long assessment on your ability to decipher AI responses. If accepted, you can get paid about $20 an hour through PayPal, according to the website.

Some tasks can take longer, depending on their difficulty and your own experience, and you'll have to take more unpaid assessments if you want to work on higher-paying projects. The tasks themselves tend to take a fair amount of mental energy, says Loper.

"The onboarding process is a little tedious. They put you through the ringer to make sure you're human and can form sentences," Loper says. "But [I've heard] it's like if you passed high school English, you ought to be able to pass this test."

Virtual assisting

Especially around the holidays, many businesses need help managing their increased workloads, says Loper. Enter virtual assistants, who remotely handle administrative business tasks like managing email inboxes, scheduling meetings, organizing Excel docs or working customer service.

Platforms like Belay and Time Etc connect virtual assistants to employers, and pay a minimum of $17 per hour once selected after an application process, according to their websites. You can find similar jobs posted directly by employers on job search websites like Robert Half, LinkedIn and ZipRecruiter, and you can advertise your virtual assistant services in Facebook groups or on freelance platforms like Fiverr.

The amount of time required probably depends on the specific job and the employer's preferences.

"Solving other people's problems" with your own skillsets can always be lucrative, Loper says. "I've hired people for content writing, for podcast editing, for video editing, website technical improvements and even. Pinterest marketing strategy. You can find support for graphic design, for editing and proofreading."

Want to make extra money outside of your day job? Sign up for CNBC's online course How to Earn Passive Income Online to learn about common passive income streams, tips to get started and real-life success stories.

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