Free Smart Bike Trainer Controller & Interval Timer
Pre & Post Workout
Why use a Warm-up?
Smart trainers need a baseline wattage to function correctly in ERG mode. If you don't set a "Warm-up Watts" value (e.g., 120W), the trainer might drop to 0 resistance or get stuck.
Warm-up
Cool-down
Main Set
Building your Interval Set
This is where you define the work. You can add steps like "Hard Effort" or "Rest".
SEQUENCE: 0:00
Rounds: Want to do 4x8min intervals? Just create the "8min Work" and "4min Rest" steps once, then set Rounds to 4.
Rounds:
SAVE & SHARE
No Login Required We save your workout structure to a public cloud database.
Community Workouts
Loading...
Round 1 / 1
READY
0W
00:00
UP NEXT: ...
System Log (Connections)
Waiting for connection...
How to use this Smart Trainer Interval Timer
JustInterval.app is a free, web-based controller for smart bike trainers. Unlike Zwift or TrainerRoad, it requires no installation, no login, and no monthly subscription. It utilizes Web Bluetooth (FTMS) to connect directly to your hardware.