While we normally get our HIIT (high-intensity interval training) fix in group fitness classes, sometimes hitting the gym isn’t in the cards. Luckily, there are several ways to reap the benefits of HIIT from the comfort of your own home. Best of all? Many of them are totally free. Here are seven of our favorites.

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1. MadFit

MadFit features real-time at home workouts, gym workouts and pretty much anything else you need for a good sweat sesh. Each video, like the 12-minute HIIT circuit above, also includes a warmup. Want more? Founder and instructor Maddie Lymburner even has her own line of cookbooks. Pretty impressive.

2. Nike Training Club

Once you download this app, you can browse tons of beginner, intermediate and advanced workouts catered to your specific equipment needs and desired intensity. Oh, and did we mention it's free all the time. The app lets you download 15-, 30- and 45-minute workouts designed by Nike trainers. Most are equipment-free and use GIFs to demonstrate how to do each exercise correctly.

3. Tone It Up

Designed by women, for women, the Tone It Up program was created to inspire and support its community of fitness lovers, with a focus on health and happiness. One of the most popular workouts is Strength Training for Beginners, which also provides info on how to choose the right weights for your needs. Heads up that some of these do require some equipment—but not all.

4. FitOn

This app’s tagline is “stop paying to work out!” which is something we can totally get behind. In its library, you’ll find a variety of classes—including cardio, Pilates and dance—from celebrity trainers and even a few celebs themselves (psst, Gabrielle Union makes an appearance).

5. Peloton

Peloton is famous for its at-home spin bikes, but good news: you don’t need one to reap the benefits of its app. According to the brand, the app acts as "your pass to thousands of live and on-demand classes" in running, yoga, strength, and, of course, cycling. And while this one isn’t free forever, Peloton is generously offering an extended three month free trial.

6. FitnessBlender

One of YouTube’s most prolific fitness channels, FitnessBlender offers more than 500 timed workouts from a 5-minute Energy Boosting Cardio Jumpstart workout to a 35-minute Upper Body Workout for Toning, all hosted by husband and wife team, Kelli and Daniel. For even more guidance, FitnessBlender offers its own home workout programs.

7. Planet Fitness

Just because you can’t go to the gym doesn’t mean the gym can’t come to you. Planet Fitness is currently offering an online program called "United We Move," with workouts being streamed live on Planet Fitness’s Facebook page daily at 7 p.m. ET and is also available to watch later if you miss it or want to do it again. Each class is led by Planet Fitness certified trainers, takes 20 minutes (or less) and doesn’t require any equipment.

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