Online Decibel Meter
Measure browser-based sound levels in dB with your microphone. No app required for everyday noise checks and reference readings.
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Sound over time
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Understanding Sound Levels
Learn how browser-based sound level readings work, why device microphones vary, and when to use certified equipment.
What is a Decibel (dB)?
A decibel (dB) is a unit used to measure the intensity of sound. It's a logarithmic scale, which means each 10 dB increase represents a 10-fold increase in sound intensity.
Key Facts:
• 0 dB is the threshold of human hearing
• Every 10 dB doubles the perceived loudness
• 80+ dB can damage hearing over time
dBA, dBC and dBZ Basics
Everyday noise guidance often uses dBA because it follows the way human hearing responds to frequency. Certified meters may also offer dBC for low-frequency or high-level sounds and dBZ for unweighted readings.
What to know:
• dBA is common for hearing and environmental noise guidance
• dBC and dBZ require calibrated equipment when accuracy matters
• Browser readings are best treated as reference estimates
Common Sound Levels Reference
Legend: Safe levels• Potentially harmful levels
Frequently Asked Questions
Is this online decibel meter accurate?
It provides browser-based reference estimates for everyday checks. Accuracy depends on your microphone, browser, device calibration, room reflections, and how you position the device. Use a certified sound level meter for medical, legal, or compliance work.
Is this a real SPL meter?
The tool estimates sound pressure level (SPL) in dB from your device microphone through the Web Audio API. It is useful as a sound level meter online, but it is not an IEC 61672 certified instrument.
What do dBA, dBC, and dBZ mean?
dBA adjusts readings toward human hearing sensitivity and is common for environmental and hearing guidance. dBC keeps more low-frequency energy for loud or bass-heavy sounds. dBZ is unweighted. Browser readings are reference estimates; use certified equipment when weighting matters.
Why do I need microphone permission?
Microphone permission lets the browser sample environmental sound levels. Audio is processed locally on your device, is not recorded, and is not uploaded to our servers.
How should I measure decibels online?
Place the microphone near the listening position, keep it clear of your hand or case, point it toward the source when possible, and watch the average, min, max, and trend for a stable reading. Avoid wind, rubbing, or tapping the device.
Why do readings vary by browser or device?
Device variation is normal. Phones, tablets, and laptops use different microphones, automatic gain controls, browser audio pipelines, and physical microphone locations, so two devices may not show the same dB value.
Phone vs laptop microphone accuracy: which is better?
A phone microphone is often closer to the sound source and less obstructed, while laptop microphones can be affected by fans, keyboard noise, and screen placement. Either can work for reference checks, but neither replaces a calibrated sound meter.
How does calibration work?
Use the calibration offset only as a reference adjustment when you have a known sound source or a certified meter to compare against. Calibration can improve consistency for one device, but it does not make a browser dB meter certified.
What should I do if microphone permission is blocked?
Open your browser or system privacy settings, allow microphone access for this site, close other apps that may be using the mic, and try Start again. If the browser does not support Web Audio or getUserMedia, use a modern Chrome, Safari, Firefox, or Edge browser.
Can I use this for OSHA, legal, or workplace compliance?
No. This online decibel meter is for everyday reference checks and education. OSHA, legal, workplace compliance, insurance, or official reports require calibrated and certified sound level meter equipment.
What is the difference between a decibel meter, sound meter, noise meter, and sound level meter?
People use these names for tools that measure decibels online or with dedicated hardware. A decibel meter, sound meter, noise meter, dB meter, and sound level meter all describe sound-level measurement, but certified meters follow strict hardware and calibration standards.
When do you need a decibel meter?
From construction sites to baby bedrooms – our sound level meter fits every noise scenario.
Concerts & Clubs
Sound levels above 100 dB damage your hearing within minutes. Measure before the show to know when ear protection is needed.
Construction & Factory
OSHA mandates hearing protection above 90 dB (8-hr average). Check if your workers need protection before damage occurs.
Baby Room & Sleep
WHO recommends below 40 dB for sleep environments. Noise above 55 dB measurably disrupts infants and children.
Office & Home Office
Office noise above 50 dB reduces productivity by up to 66%. Identify noise sources and create a focused workspace.
When does noise become dangerous? The 85 dB threshold
The human ear is built for quiet environments. Above 85 dB, hair cells in the inner ear begin to die — permanently. The louder the sound, the faster the damage accumulates.
Online decibel meter vs. professional sound level meter
🌐 Browser Decibel Meter (this tool)
- ✓Free & instant — no setup
- ✓No download required
- ✓Reference measurements for everyday use
- ✓Works on any device with a microphone
- ○Not IEC 61672 calibrated
- ○Not suitable for legal or regulatory purposes
- ○Accuracy varies by device microphone
🔬 Professional Sound Level Meter (Class 1/2)
- ✓IEC 61672 / OSHA certified
- ✓Suitable for regulatory compliance
- ✓±0.5 dB accuracy
- ✓Data logging and report generation
- ○Cost: $100–500
- ○Requires periodic calibration
For certified workplace noise measurements, we recommend a Class 2 sound level meter:
Recommended Products
This section contains Amazon affiliate links. We may earn a small commission at no extra cost to you.
Loop Experience 2
If our meter shows 85 dB+, protect yourself. Loop Experience 2 filters harmful noise while preserving music quality – for concerts, commutes, and everyday life.
3M Peltor SportTac
Professional electronic earmuff for workplace use. Amplifies quiet sounds while blocking dangerous noise spikes above 82 dB. Built for construction and industry.
Class 2 Sound Level Meter
Browser meters are great for reference. For certified workplace compliance (OSHA, EU), upgrade to a calibrated Class 2 SLM with IEC 61672 certification.