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⏱ Countdown Timer & Stopwatch

Unified countdown timer and stopwatch with up to 10 concurrent timer cards, natural-language input, serialized alarm queue, local restore, cross-tab sync, voice announcements, custom preset editor (drag-reorder, color-coded, shareable link), 15 ready presets (Pomodoro, Tabata, egg, ramen, meditation, meeting), multi-step engine, Web Audio bells, Wake Lock, fullscreen big display, and shareable URL. Timers run in the current browser with no login required and do not rely on a LittleOne Tools timer backend.

Accepts colon, units, Chinese, ISO 8601, natural language
Settings
70%
🔊 Voice announcements (off)
Triggers
1.0×
1.0
100%
Custom phrases (140 chars, {phase-name} / {remaining} tokens)
Recent History (0)
    This tool runs in the current browser with no login required and does not rely on a LittleOne Tools timer backend.
    FAQ
    Is the timer accurate when the tab is in the background?

    We anchor to the wall clock via setTimeout(fire) plus visibilitychange recalibration. Browsers throttle background tabs, so the fire can be delayed 1-5 s. For critical timers keep the tab visible or enable "System notification".

    Will it still fire if I close the tab?

    No. This tool runs in your browser; closing the tab stops everything. Refreshing the page automatically restores an in-progress countdown (by replaying from the saved start epoch).

    Can iOS Safari vibrate?

    No. iOS Safari does not support the Vibration API — we skip silently. Sound, visual notifications, and system notifications (PWA mode only) still work.

    Why is there no sound until the first Start click?

    Browsers require a user gesture to unlock AudioContext (iOS Safari is especially strict). The first Start click unlocks audio; all subsequent bells will play.

    Which input formats are supported?

    Colon (1:30:00 / 5:30), unit expression (1h30m / 90s), Chinese natural language, ISO 8601 (PT1H30M), and bare numbers (interpreted as seconds). Maximum 24 hours.

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    Unified countdown timer & stopwatch with up to 10 concurrent countdown cards in one local workspace. Supports 5 input formats (colon, units, Chinese natural language, ISO 8601, bare number), 15 ready presets (Pomodoro 25/5×4, Tabata 20/10×8, soft/medium/hard boiled egg, ramen 3 min, coffee bloom, green tea, meditation 10/15/20, meeting 30/45/60), multi-step engine, serialized alarm queue, local restore, cross-tab sync, 5 synthesized Web Audio bells, system notifications, vibration, Wake Lock, fullscreen big display. Stopwatch supports lap splits with fastest/slowest markers, CSV export, and an SVG bar chart. At-time countdown, shareable URL, keyboard shortcuts (Space/R/L/F/Esc), tiered screen-reader announcements, 44 px touch targets, portrait/landscape adaptive. Timers run in the current browser with no login required and do not rely on a LittleOne Tools timer backend.