HazelStack

Pick a routine, press play, and follow the ring. Hazel Stack is an interval timer for Tabata, circuits, EMOM and ladder workouts. You can also build your own routine in about a minute.
READY THE MOMENT YOU OPEN IT
Ten routines come preloaded: Tabata Classic, Full-Body Circuit, Core Crusher, EMOM Ten, Sprint Ladder, Mobility Flow, Upper Body Pump, Leg Day Ladder, Beginner Burn and Desk Reset. Duplicate any of them and change whatever you like.
BUILD YOUR OWN
Set the prep, work, rest and round-break times, plus the number of rounds
Add movements from a built-in library of 38 exercises covering full body, core, upper body, lower body, cardio and mobility. Each one has a short form cue
A preview strip shows every interval in your routine at a glance, and the total length updates as you edit
A TIMER YOU CAN READ FROM ACROSS THE ROOM
The main dial shows the current block draining away. Around it, a segmented track gives each interval its own arc, coloured by phase. An optional "up next" card, an oversized countdown and a ring that flashes in the final seconds let you keep training without squinting at your phone. Skip forward, restart a block, or pause whenever you need to.
TRACK THE WORK
Every session goes into your log. Watch your weekly minutes against a goal you set, keep your day streak going, fill in the 30-day consistency grid, and unlock 12 badges along the way.
PRIVATE AND OFFLINE
No account, no ads and no tracking. Hazel Stack never connects to the internet. Your routines and history are stored on your phone and nowhere else.
Dark theme built for early mornings, with a reduced-motion option.