Decibel meter: how loud is your room, really?
Your microphone shows the room’s sound level live in dB(A), A-weighted like a sound level meter so the number follows what your ear hears. Nothing is recorded: the page only reads the level.
Measure the noise
Your browser will ask for microphone access. Readings are approximate; you can calibrate them below.
Calibrate0 dB
A browser doesn’t know how sensitive your mic is, so the reading assumes a typical laptop mic. If you have a sound level meter you trust, measure the same steady sound with both and move this number until they match. The setting stays in this browser.
How the meter works
Weighted for the ear
Our hearing is far less sensitive to low rumble than to mid tones, so sound meters apply A-weighting. A 100 Hz hum counts about 19 dB less than a 1 kHz tone of the same strength, and the meter does the same.
Fast response
The live number follows the sound with a 125 ms time constant, the “fast” setting of a standard sound level meter. Peaks show without the reading jumping on every click.
A true average
The average is an energy average (Leq), not the mean of the numbers on screen. A few loud moments count for all the energy they carry, which is how noise standards average sound.
Why the numbers are estimates
The browser passes on the mic signal but not how sensitive the mic is. The meter switches off the browser’s automatic volume and noise suppression so they can’t skew the reading, but the number is still an estimate. Compare rooms and times of day on the same device, or calibrate to get closer to real figures.
Typical noise levels
Rough figures to place your reading. Real rooms vary by a few decibels either way.
- 30 dB(A)
- Quiet bedroom at night, a whisper
- 40 dB(A)
- Library, quiet home office
- 50 dB(A)
- Quiet street outside a window, moderate rain
- 60 dB(A)
- Normal conversation, busy office
- 70 dB(A)
- Vacuum cleaner, loud TV
- 80 dB(A)
- Busy street, kitchen blender
- 90 dB(A)
- Hair dryer close up, lawn mower
What the number means for calls
Under 40 dB(A) a room is quiet enough for calls and recording. Between 40 and 50 it is fine for calls, though a sensitive mic will pick up the room in your pauses. Above 50 the people you talk to will hear the fan, the street or the kitchen, and above 60 a call needs noise suppression to stay clear.
What matters most is how far your voice rises above the room. The free mic test measures exactly that, together with echo and clarity.
Test your micQuestions
Is anything recorded?
No. The page reads the level of the sound many times a second and shows the number. No audio is stored, and nothing is sent to our server or anyone else’s.
How accurate is it?
Without calibration, expect it to be off by several decibels on a laptop mic and more on a USB mic or headset, because every mic has a different sensitivity. For comparing rooms or times of day on the same device it works well. For legal or workplace measurements use a certified sound level meter.
Why does my phone app show a different number?
Each app assumes a different mic sensitivity and may use different weighting. Measure the same steady sound with both and use the correction setting to line them up.
Does it work on a phone?
Yes, in a current mobile browser. Some phones process the mic signal on their own, which can flatten loud sounds.