Free Online Sound Meter
Measure noise levels in real time with this browser-based sound meter and decibel meter — no app, download, or sign-up required. Just allow microphone access and press start.
Hearing safety: Start measuring to check the noise level in your environment.
Note: This online sound meter is a reference-only estimate. Device microphones vary, so results may be shifted — use the calibrate control above to align the reading against a known source. For legal or occupational compliance, use a professional class-1 or class-2 meter. Quiet room ≈ 30–40 dB, conversation ≈ 60 dB, city traffic ≈ 80 dB.
Measurement History
What Is This Online Sound Meter?
This free online sound meter turns your phone, tablet, or computer into a real-time noise-measuring tool. The sound meter samples audio from your microphone and shows how loud your surroundings are in decibels (dB). Because it runs entirely in your browser, there is nothing to install: open the page, allow microphone access, and it starts reading instantly.
We originally built this sound meter to help shoppers compare the noise of portable air conditioners, but it works just as well for a noisy office, a neighbour's music, traffic outside your window, or a quiet bedroom at night. Whenever you want a quick, no-cost noise reading, this sound meter and decibel meter is ready to use.
Sound Meter vs Decibel Meter: Are They the Same Thing?
A sound meter and a decibel meterdescribe the same instrument. It measures how loud a sound is and reports that loudness in decibels — which is exactly why people call a sound meter a decibel meter. Professionals may also say "sound level meter" or "SPL meter", but for everyday use the two terms mean the tool above.
A professional decibel meter is a calibrated hardware device that measures physical sound pressure (dB SPL). This browser-based sound meter estimates that value from your device microphone, then lets you fine-tune the reading with the align control. That makes our online sound meter ideal for comparing sources and getting a solid ballpark figure, while a certified unit remains the right choice for legal or occupational compliance.
Decibel Meter Chart: Common Sound Levels
Use this decibel chart to understand what a sound meter reading means. Compare the number shown on the meter above with the everyday examples below to judge whether a noise is quiet, loud, or loud enough to harm your hearing.
| Sound Meter Reading | Typical Example | Loudness |
|---|---|---|
| 0–20 dB | Threshold of hearing, rustling leaves, a soft whisper | Very Quiet |
| 30 dB | Quiet bedroom at night, a library reading room | Quiet |
| 40 dB | Quiet office, a modern quiet portable air conditioner | Quiet |
| 50 dB | Moderate rainfall, a household refrigerator | Moderate |
| 60 dB | Normal conversation, a typical portable AC on low fan | Moderate |
| 70 dB | Vacuum cleaner, busy road traffic | Loud |
| 80 dB | City traffic, an alarm clock, a loud AC unit | Loud |
| 85 dB | Hearing-damage risk begins with prolonged exposure | Harmful |
| 90–100 dB | Lawnmower, motorcycle, nightclub | Very Loud |
| 110–120 dB | Rock concert, chainsaw, ambulance siren (pain threshold) | Dangerous |
As a rule of thumb, any sound meter reading below 70 dB is safe for unlimited time, 85 dB is where hearing-damage risk begins, and readings above 100 dB can harm your ears quickly.
How to Use the Sound Meter
- 1Press Start Measuring and allow microphone access so the sound meter can hear your environment.
- 2Watch the large decibel reading, the Min / Avg / Max stats, the live spectrum, and the 30-second history graph update in real time.
- 3Hold your device steady near the noise source and let the sound meter run for 30–60 seconds so the average settles.
- 4If the reading looks too high or too low in a silent room, use the Align reading buttons to calibrate the sound meter to your device.
Using the Sound Meter to Check Air Conditioner Noise
Point the sound meter at your portable air conditioner to see exactly how loud it runs. You can compare one AC unit against another, or against everyday household appliances, so you can pick the quietest option. Here is how to read the sound meter results for air conditioner noise.
Very Quiet (under 40 dB)
Ideal for bedrooms. A sound meter reading under 40 dB means the AC is whisper-quiet.
- • Perfect for bedrooms and nurseries
- • Won't disturb sleep or work
- • Premium AC units hit this level
- • Best measured at night
Moderate (40–60 dB)
Acceptable for living areas — the sound meter shows a typical, noticeable AC.
- • Suitable for living rooms and offices
- • Noticeable but not disruptive
- • Most standard AC units land here
- • Test at each fan speed
Too Loud (over 60 dB)
Loud for a home. If the sound meter shows these levels, consider alternatives.
- • Disruptive to sleep and conversation
- • May be uncomfortably loud
- • Consider sound dampening or replacement
- • Compare other units to find quieter ones
Sound Meter Best Practices for AC Testing
- • Hold the sound meter about 1 metre (3 feet) from the AC unit
- • Take every measurement from the same spot
- • Check the reading at each fan speed and mode
- • Record the sound meter average and maximum for comparison
- • Compare against other appliances for context
Sound Meter Privacy & Security
Your Privacy First
- This sound meter runs entirely in your browser — no audio is sent to our servers
- Every measurement is processed locally on your device
- No recordings or audio files are ever stored
- You can revoke microphone access at any time
Device Compatibility
- The sound meter works on smartphones, tablets, and computers
- Compatible with Chrome, Firefox, Safari, and Edge
- A built-in microphone is all it needs
- No app install required — use the sound meter instantly
Sound Meter FAQ
How accurate is this online sound meter?
This sound meter gives a reliable decibel estimate for comparing sounds. Because it reads from your device microphone, it is not a calibrated laboratory decibel meter — but once you align the reading, the sound meter is accurate to within a few decibels. For scientific or legal testing, use a professional decibel meter.
Is a sound meter the same as a decibel meter?
Yes. A sound meter and a decibel meter are the same tool — both measure loudness and report it in decibels. You may also see the sound meter called a sound level meter or SPL meter, but they all do the same job.
Can I use the sound meter on my phone?
Yes — the sound meter is fully optimised for mobile. Your smartphone's built-in microphone is all it needs, and the interface adapts automatically to your screen size for the best experience.
Why does the sound meter reading fluctuate?
Sound meter readings naturally rise and fall because real-world noise is never perfectly steady. The average (AVG) value is the most useful figure for judging overall loudness, while the max shows the loudest peak the sound meter captured.
How do I get the most accurate sound meter readings?
For the most consistent sound meter measurements:
- Hold the sound meter 1–2 metres from the sound source
- Keep it at the same height for every reading
- Minimise background noise when comparing sounds
- Let the sound meter run 30–60 seconds and use the average
- Make sure nothing is covering the microphone
- Calibrate the sound meter with the align control in a quiet room
Related Tools & Resources
BTU Calculator
Find the right cooling capacity for your room before you test an AC unit with the sound meter.
Energy Cost Calculator
Estimate running costs for the quiet AC units you shortlist.
Noise Level Guide
A full guide to interpreting your sound meter readings and AC noise standards.
Pro Tip: Pair the sound meter with our other tools to balance cooling performance, energy efficiency, and quiet operation — it tells you which portable air conditioner is truly the quietest.