Noise meter — measure how loud it is with your phone or laptop
Noise meter
Press Start and allow the microphone. Sound is measured in this tab — nothing is recorded or sent anywhere.
Estimate — a phone or laptop microphone is not a calibrated sound level meter.
Press Start to measure.
- Min
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- Average (Leq)
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- Max
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- Time
- 0:00
Calibrate against a reference meter
If you have a sound level meter you trust, measure the same steady sound with both and nudge this reading until they match. The adjustment is kept only while this tab is open.
A noise meter measures how loud the sound around you is, in decibels. This one uses your phone or laptop microphone to show a live dBA reading with minimum, maximum and average level — in the browser, without recording anything. Treat the number as an estimate: the microphone isn’t a calibrated instrument.
Below: how the meter works, whether a phone can stand in for a dB meter, how to check noise at home or in a classroom, and what the readings mean for hearing.
Sound meter online
An online sound meter reads the level of your microphone signal and converts it into decibels. This one applies the A-weighting filter, which lowers very low and very high pitches the way human hearing does, and shows the result as dBA. Switch to Flat to see the unweighted level.
| Setting | What it does | When to use it |
|---|---|---|
| A (dBA) | Weights frequencies like human hearing | Hearing-related questions — NIOSH recommends A-weighting |
| Flat (dB) | No frequency weighting | Low rumble, such as traffic or bass through a wall |
| Fast | Averages over 125 milliseconds | Short bursts: a door slam, a dog bark |
| Slow | Averages over 1 second | Steady noise — NIOSH recommends Slow response |
| Average (Leq) | Averages sound energy over the session | One number for a whole period, like a noisy hour |
The average is energy-based, not a plain mean of the numbers on screen. One loud minute in a quiet hour pulls the average up far more than the displayed readings suggest, which matches how noise exposure is assessed.
Can you use your phone as a dB meter?
A phone can work as a dB meter for everyday checks, with a clear limit. The US National Institute for Occupational Safety and Health says sound measurement apps can provide a measure of area noise but may not comply with regulatory requirements. For workplace measurements NIOSH advises a Type 1 or Type 2 sound level meter, calibrated before and after use.
Good for comparisons
Same phone, same spot, same settings: before and after closing a window, or day against night.
Not for official numbers
Microphones differ between devices, and none of them is calibrated the way a sound level meter is.
Calibrate if you can
With a reference meter at hand, measure one steady sound with both and adjust this reading to match.
How to check the noise level in your house
Checking the noise level in a house takes a few steady measurements rather than one quick look. NIOSH’s own advice for mapping noise is to measure each location for at least 30 seconds to capture noise that comes and goes.
Step 1
Pick the spot that matters
Where you sleep or work, not next to the source. Keep the phone away from your body.
Step 2
Set A and Slow
The settings NIOSH recommends for sound level measurements.
Step 3
Measure a quiet baseline
Reset, then record at least 30 seconds when the noise is absent.
Step 4
Measure the noise
Reset again and record at least 30 seconds while the noise is present.
Step 5
Compare the averages
The difference between the two Leq values tells you how much the noise adds.
For a neighbour’s music or a street, write down the date, time and both averages each time. A consistent log from the same device shows a pattern even when the absolute number is only an estimate.
Noise meter for the classroom
A noise meter for the classroom works best as a shared visual cue rather than a precise instrument. Put the page on a projected screen, choose Slow response so the number doesn’t jump with every word, and agree on a level band the class aims to stay in.
The coloured bar changes at 85 dBA, the level where NIDCD says long or repeated exposure can cause hearing loss. A classroom should sit far below that. The band text under the reading describes each range in plain words, so students can see “around normal conversation” instead of a bare number.
What the readings mean for hearing
Decibel readings map to hearing risk through two thresholds from US health agencies. NIDCD says sounds at or below 70 dBA are unlikely to cause hearing loss even after long exposure, while long or repeated exposure at 85 dBA and above can cause it.
85 dBA over 8 hours
| Sound | Typical level (NIDCD) |
|---|---|
| Normal conversation | 60–70 dBA |
| Movie theater | 74–104 dBA |
| Motorcycles and dirt bikes | 80–110 dBA |
| Music through headphones at maximum volume, sporting events, concerts | 94–110 dBA |
| Sirens | 110–129 dBA |
| Fireworks show | 140–160 dBA |
NIOSH adds a simple check that needs no meter: noise is likely hazardous if you must raise your voice to talk with someone an arm’s length away. If a phone speaker sounds weak when you compare levels, the online speaker test and the water eject tone check the speaker itself, and the guide to a phone that plays too quietly covers volume settings.