Free Online Interval Timer for HIIT, Tabata & Boxing
Engineered for athletes, personal trainers, and home fitness enthusiasts. Experience zero-drift interval pacing, loud synthesized gym audio cues, automatic screen wake-lock, and zero disruptive ads.
100% Distraction-Free
Zero banner ads, video popups, or paywalls. Open the browser, select your protocol, and focus entirely on your physical performance.
Screen Wake Lock
Integrated with the native Screen Wake Lock API to prevent your phone, tablet, or computer display from going to sleep during workout sets.
Gym Audio Profiles
Loud boxing ring bells, sports whistles, and 3-2-1 countdown beeps synthesized directly via Web Audio API. Zero external audio downloads.
Gym Screen Contrast
Massive tabular figures and high-contrast color shifts (Vibrant Green for Work, Coral Red for Rest) clearly visible from 20 feet away across a gym.
Master Your Training: Supported Protocols & Formats
🔥 Tabata Protocol (20s / 10s)
The world's most scientifically validated interval routine. Perform 20 seconds of all-out maximum effort (burpees, sprints, kettlebell swings) followed by 10 seconds of rest for 8 consecutive rounds (4 minutes total).
⚡ High-Intensity Interval Training (HIIT)
Standard 30/30 and 40/20 cycles balance anaerobic burst work with sufficient cardiovascular recovery. Ideal for circuit training, calisthenics, rowing machines, and assault bike intervals.
🥊 Boxing & Sparring Rounds
Standard 3-minute rounds with 1-minute recovery matching competitive amateur and professional boxing rules. Use with heavy bags, shadowboxing, pads, or martial arts sparring drills.
Frequently Asked Questions
Everything you need to know about using this tool with maximum precision and ease.
What is an interval timer and how does it work?
An interval timer is a specialized workout clock that alternates between high-intensity exercise periods (Work Phase) and low-intensity recovery periods (Rest Phase) across a predetermined number of sets or rounds. Unlike a simple countdown timer, an interval timer automatically transitions between work and rest cycles, triggering audio cues so you don't have to touch your phone or watch during training.
What is the Tabata protocol (20/10 interval)?
Developed by Japanese scientist Dr. Izumi Tabata, the Tabata Protocol consists of 8 rounds of 20 seconds of maximum-effort work followed by 10 seconds of complete rest, totaling exactly 4 minutes. It is scientifically proven to boost both aerobic and anaerobic cardiovascular capacity in minimal time. Click our Tabata (20/10) preset to start immediately.
How do boxing and sparring rounds work on this timer?
Traditional professional and amateur boxing rounds consist of 3 minutes of active sparring or heavy bag work followed by 1 minute of corner rest. Our Boxing preset triggers an authentic brass boxing bell gong at the start and end of every round, with 3-2-1 warning beeps before the bell rings.
Will my phone screen turn off or lock during a workout?
No! UTENIQ utilizes the modern browser Screen Wake Lock API. As long as your workout timer is actively running, your phone, tablet, or laptop screen will remain completely awake, so you never lose track of your intervals in the middle of a set.
Can I use this interval timer for CrossFit WODs like EMOM and AMRAP?
Yes. Our EMOM (Every Minute On the Minute) preset sets 60-second work intervals with 0-second rest for 10 to 20 rounds. You perform your prescribed exercise reps at the start of every minute and rest for whatever time remains before the next round bells.
Is this interval timer completely free without ads?
Yes, 100% free with zero banner ads, no popups, and no account signup required. It runs directly inside your web browser with high-contrast colors designed to be easily readable from across a gym floor or living room.