Free 30-30 interval timer for equal work-rest HIIT training. 30 seconds of hard effort followed by 30 seconds of recovery — versatile for all fitness levels.
The 30-30 (1:1 work-to-rest) is the most beginner-friendly HIIT ratio. The equal rest period allows more recovery than Tabata's 20-10, making it sustainable for 10–15 rounds. It's also excellent for general fitness maintenance and for anyone building up to more demanding protocols like Tabata.
30-30 intervals work best at 80–90% effort (hard but not absolutely maximal). This is harder than steady-state cardio but below the all-out intensity of Tabata. You should be breathing hard and unable to hold a normal conversation, but you should be able to sustain that pace for all planned rounds.
30 seconds is versatile: burpees, squat jumps, mountain climbers, jumping jacks, jump rope, cycling sprint, rowing, battle ropes. The extra 10 seconds vs Tabata allows slightly more complex movements and better acceleration time. 30-30 is also popular for skill-based sports drills where you need some setup time.
10–15 rounds is standard. 10 rounds = 10 minutes of active work. 15 rounds = 15 minutes. With warm-up and cool-down, a 30-30 workout runs 25–30 minutes total. This is an efficient, well-rounded workout. Beginners: start at 8 rounds and add 1–2 rounds per week.
Either works: active rest (walking, slow jogging, light movement) maintains elevated heart rate and keeps the session more aerobic. Passive rest (standing still, catching breath) allows slightly better recovery for higher effort in the next work period. Choose based on your goal: aerobic conditioning (active rest) or power/speed (passive rest).