90분 타이머는 어디에 쓰나요?
Ultradian rhythm focus block
Sleep researcher Nathaniel Kleitman's original ultradian-rhythm work — extended by Tony Schwartz and others — points to roughly 90-minute cycles in waking cognition as well as in sleep. Many serious deep workers use a 90/20 ratio: ninety minutes locked in, twenty off. The interval is long enough for genuine depth and short enough to recover within a workday.
Yoga, Pilates, and long workout sessions
The standard length of a Vinyasa or Ashtanga class, a Pilates reformer session, or a long strength-and-conditioning workout. Ninety minutes is also the time it takes to do a real sport-specific endurance ride or run. Use the LED on a phone propped against the mat or bench.
Half a movie / long feature first half
Most modern feature films run 100–140 minutes, with the natural intermission point near 90. Use the timer if you are watching at home with a hard exit time.
이 타이머 사용법
- Click Start 90-Minute Timer above. The countdown opens at 1:30:00 and begins immediately.
- 자리를 비워도 됩니다. 선명한 빨간색 7 세그먼트 LED는 방 건너편에서도 보이며, 탭을 활성 상태로 둘 필요가 없습니다.
- 탭 전환은 자유롭게 하세요.
performance.now()로 절대 종료 시각을 기준으로 계산하므로 백그라운드 스로틀링이 타이머를 느리게 하지 않습니다. - 0이 되면 3음 차임이 울리고, LED가 깜빡이며, 탭 파비콘이 빨갛게 변해 한 번에 완료를 확인할 수 있습니다.
- 스페이스 키(또는 Reset 탭)로 다시 실행. 1〜8로 다른 프리셋으로 이동할 수 있습니다.
자주 묻는 질문
- Why 90 minutes for deep work?
- Multiple studies — Ericsson's musician work, Schwartz's HBR papers, sleep-stage research — converge on 90-minute ultradian cycles as a natural work-recovery rhythm for humans.
- Will the bell wake me from a 90-min nap?
- A 90-minute nap completes one full sleep cycle, often leaving you refreshed rather than groggy. The chime is loud enough to wake from REM but may struggle through deep slow-wave sleep. Set a backup phone alarm if the stakes are high.
- Does the favicon flash for the whole bell duration?
- Yes — it stays red until you reset or close the tab.
- Can I add a 45-minute halfway beep?
- Phase 1 does not have midpoint cues. The Pomodoro tool with a 45/0 chained preset is a workaround.