Zero-Drift Background Clock
Browsers throttle main-thread timers down to once a minute when tabs lose focus or screens sleep. SpinFoundry's interval timer executes inside a dedicated inline Web Worker synchronized with monotonic timestamps (performance.now()), ensuring zero timer drift. Screen Wake Lock prevents displays from sleeping during active sets.
Precision Training Gear
Gymboss Interval Timer & Stopwatch
Classic tactile vibration timer for CrossFit, combat sports, and outdoor sprinting.
Polar H10 Heart Rate Chest StrapMedical-grade ECG heart rate monitoring for precision high-intensity threshold pacing.
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