Online Metronome

About Online Metronome

How to use Online Metronome

1. Open the page and the metronome is immediately ready to use. Check the current tempo displayed as a large BPM number in the center (default: 120 BPM), then adjust to your desired tempo using the slider, number input field, or the +/- increment buttons.
2. Select the time signature for your practice piece from the time signature buttons. The default is 4/4, but choose 3/4 for waltzes, 2/4 for marches, or 6/8 and 7/8 for compound and odd meters. Keyboard shortcuts (keys 1–5) allow quick selection.
3. Press the large Start button to begin the metronome. Beat indicator dots will light up on each beat — red accent on beat 1, blue on subsequent beats. Press again to stop. You can also use the Space key to toggle playback.
4. If you do not know the tempo of a song, tap the 'Tap Tempo' button rhythmically several times and the BPM will be automatically detected and applied. You can also select a representative tempo with one click from the tempo presets (Largo through Presto).
5. Keyboard shortcuts: Use up/down arrow keys to adjust BPM by ±1, press B to activate tap tempo, or Space to toggle playback. Fully keyboard-accessible.

Benefits of Online Metronome

• [Ultra-Precise Timing via Web Audio API] While typical browser metronomes depend on JavaScript's inherently imprecise setInterval — which can drift by tens of milliseconds due to garbage collection and rendering — this tool implements a lookahead scheduling algorithm anchored to AudioContext.currentTime. Because audio scheduling runs on a separate thread from the browser's main UI thread, it maintains rock-solid, professional-grade precision even when the browser is momentarily busy, meeting the exacting requirements of professional performers and studio musicians.
• [Versatile Time Signatures and Tempo Presets for Instant Practice] Switch between five time signatures (2/4, 3/4, 4/4, 6/8, 7/8) with a single tap, and choose from six tempo presets ranging from Largo (40-60) to Presto (168-200). The BPM range extends from 20 to 300, covering everything from ultra-slow foundational exercises to blazing-fast technical drills across every musical genre and difficulty level. Visual beat indicator dots display each beat in color, allowing precise rhythm tracking even without headphones.
• [Tap Tempo, Keyboard Shortcuts, and Bilingual Tempo Display for Rapid Control] When you do not know the tempo of a piece you want to practice, simply tap the Tap Tempo button rhythmically while listening, and the tool automatically calculates BPM from your recent tap intervals and applies it instantly. Full keyboard control (Space for play/stop, arrow keys to adjust BPM, 1–5 for time signatures, B to activate tap tempo) enables hands-on-keyboard workflows. Tempo markings display in both English and Japanese (Largo, Adagio, Andante, etc. — ラルゴ、アダージョ、アンダンテ等), making the tool ideal for classical music education and international ensembles.