Classroom / Noise
Classroom Noise Meter (Visual Volume Monitor)
Show the class how loud it is: a big bar that turns from green to amber to red when the room gets too loud, with an optional chime and a full-screen view for the board. Works with the computer's microphone.
Classroom Noise Meter (Visual Volume Monitor): The microphone level is turned into a scale from 0, a silent room, to 100, shouting near the microphone, and smoothed so it rises quickly and falls slowly. The board turns amber as the level nears the line and red once it has stayed above it for a second and a half, so a single bang does not count; it also counts how often the room got too loud. Runs 100% locally in your browser with zero server file uploads.
- Category
- School & study tools
- Runs
- In your browser
- Cost
- Free · no sign-up
- Availability
- Ready to use
Runs entirely in your browser
The level is relative, from 0 for a silent room to 100 for shouting near the microphone, not decibels: microphones and browsers differ, so set the line by trying it with your class. It turns red after more than a second and a half above the line, so a single bang does not count. Nothing is recorded or sent; the sound is only measured, in your browser.
Setting it up
Start the meter during quiet work and note where the bar sits, then during normal group work. Set the line a little above the group-work level, so it only turns red when the room really gets loud.
Explain the colours to the class first: green for quiet work, amber as a warning, red to stop and reset. For a timed activity alongside it, use the online timer.
Why it is not in decibels
A decibel reading needs a calibrated microphone; laptop and tablet microphones differ by many decibels and change their sensitivity. The meter's 0 to 100 scale stays consistent on one device in one place, which is what matters in a classroom.
For an approximate decibel reading, use the sound level meter, which can be calibrated against a known level.
How to use it
- Press Start listening and allow the microphone.
- Set the line for too loud by trying it with the class.
- Put it on full screen on the board; it turns red and can chime when the room stays over the line.
Privacy & limitations
The sound is measured in your browser and never recorded or sent.
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Frequently asked questions
Is the number in decibels?
No: microphones, laptops, and browsers differ too much for that, so it is a relative scale. For an estimate in decibels, use the sound level meter.
Where should the computer go?
Somewhere central and at the same spot each day, since the reading depends on how far the microphone is from the class.
Why does the screen not go to sleep?
The meter asks the browser to keep the screen on while it is listening, where the browser supports it.
Free tool · runs in your browser · no account required