Timer
00:00:00
Ready.
How timing stays accurate
The timer builds a finite phase timeline from preparation, work, rest, and round settings. Current phase and round derive from monotonic elapsed time, so a delayed callback can cross several boundaries and still resume in the correct phase.
Worked example
The Tabata-style preset uses 20 seconds of work, 10 seconds of rest, and 8 rounds. It is one preset; not every interval workout is Tabata.
Limits and browser behavior
Work is 1–3,600 seconds, rest 0–3,600 seconds, preparation 0–60 seconds, and rounds 1–999. Browser or device suspension may delay audible cues even though the displayed timeline catches up when execution resumes.
Sound is generated locally after a user action. No remote audio file, notification permission, wake lock, microphone, or recording is used.
Privacy and accessibility
Timer values remain page-memory only and disappear when the tab is reloaded. Buttons are keyboard operable, state and phase changes are announced without announcing every tick, and reduced-motion preferences disable decorative motion without changing timing.