Full Session Log
Workout Activity Tracker
Pace a whole 60–90 minute session in phases, log sets and reps, then export to CSV.
Fitness & Interval Training
Train to the beat.
Gym-wall LED clocks, authentic bells and buzzers, and a full-session tracker. Free to use, distraction-free, and works offline.
- Zero-latency audio
- Screen wake lock
- CSV export
- 100% private
The complete toolkit
Pick your session
Max-Effort Cardio
Tabata 20/10
8 rounds of 20s all-out, 10s rest.
Barbell & Density
EMOM 20m
Every Minute on the Minute pacing for lifting and calisthenics.
Combat Pacing
Boxing & MMA
3m rounds, 1m rest.
Metabolic
Circuit HIIT 45/15
45s work, 15s to switch.
Configurable
Custom Builder
Set your own work, rest and rounds.
Quick guide
Which timer for today's workout?
| Timer | Timing | Best for | Sound | |
|---|---|---|---|---|
| Activity Tracker | Full workout | Lifting & full gym sessions | Phase chime | Launch → |
| Tabata | 20s / 10s × 8 | Max-effort cardio, fat burn | Industrial buzzer | Launch → |
| EMOM 20m | 1 min × 20 | Barbell cycling, density work | Minute chime | Launch → |
| Boxing / MMA | 3m / 1m | Sparring & combat rounds | Brass bell + clacker | Launch → |
| HIIT 45/15 | 45s / 15s | Circuits & conditioning | Coach whistle | Launch → |
Engineered for athletes
No popups mid-set. No lag. No sign-up.
Anchored to a performance.now() hardware loop with Screen Wake Lock, so it never drops an interval. Every bell, whistle and clacker is synthesised locally with the Web Audio API — and the whole thing works offline.
- Zero audio lagProcedural Web Audio
- Wake lockScreen stays on during sets
- No popupsNo video between rounds
- 100% privateLogs stay in your browser
Athlete FAQs
Questions, answered
Activity Tracker vs interval clocks — what's the difference?
The Activity Tracker manages your whole 60–90 minute session in phases, logs sets and reps and exports CSV. The interval clocks (Tabata, EMOM, Boxing, HIIT) pace short work/rest rounds with split-second audio cues.
Will the timer stop if my phone screen locks?
No. The Screen Wake Lock API keeps the display on during workouts, and timers use hardware timestamps so they stay in sync even when the tab is minimised.
Does it work offline in a garage gym?
Yes. Once loaded, timers, audio and logs all run locally on your device with no server calls.
Are the bells and buzzers real audio files?
No — they're synthesised live with the Web Audio API, so there's no download lag and no audio latency.