The noise meter listens to the room through your mic, runs a small ball-physics simulation on screen, and flashes a friendly warning when the class gets above your chosen quiet line. Audio is analysed locally — nothing is recorded or sent anywhere.
What you'll be able to do
- Project a live noise visualiser the whole class can see
- Set a quiet threshold and warning message for your room
- Adjust sensitivity and ball shape to match your year group
Step by step
- 1
Open the tool
Sidebar → Teaching tools → Classroom noise meter.
- 2
Start the microphone
Click Start listening and accept the browser's mic prompt. Audio is analysed on-device — KMF never records or transmits it.
- 3
Pick a quiet threshold
Use the Calm / Group / Active quick-set buttons or drag the slider in Settings. Above the threshold the warning overlay flashes.
- 4
Project full-screen
Click the fullscreen button (top-right). Adjust ball count, shape, and warning text in Settings so it matches the tone you want.
Audio stays on the device
We only read the analyser's live RMS level. No PCM is stored, no recording is created, nothing is sent over the network.
Hush mode
Pair the noise meter with the Classroom timer's Shh-noise tone — set a 60-second 'noise check' and let the balls speak for themselves.