Online Decibel Meter — Free Sound Level Meter (Live)
An online decibel meter uses your device microphone to show how loud your surroundings are in real time. Because phone and laptop mics are uncalibrated, it gives a relative loudness reading for comparison, not a certified SPL measurement — everything runs privately in your browser.
Runs entirely in your browser using your microphone. No audio is recorded or uploaded. For legal or safety measurements, use a calibrated sound-level meter.
This free online decibel meter uses your device’s microphone to show how loud your surroundings are, live, right in your browser. It’s a quick, private way to compare noise levels — no app, no sign-up, and nothing is recorded or uploaded.
Important: this is a relative reading
Phone and laptop microphones are not calibrated and every device is different, so the number shown is a relative loudness indicator for fun and comparison — not a certified sound-pressure-level (SPL) measurement. For legal, workplace or safety decisions, use a properly calibrated sound-level meter.
Everyday noise levels for reference
| Approx. level | Typical source |
|---|---|
| 30 dB | Whisper, quiet library |
| 40–50 dB | Quiet home, light rain |
| 60 dB | Normal conversation |
| 70 dB | Busy traffic, vacuum cleaner |
| 85 dB | Heavy traffic — prolonged exposure can harm hearing |
| 100–110 dB | Concert, power tools |
| 120 dB+ | Jet engine nearby, threshold of pain |
These are general public-reference figures for context, not measurements taken by this tool.
How to use it
- Tap Start measuring and allow microphone access.
- The live number and bar show the current relative level; the peak is tracked separately.
- Tap Reset peak to start a new peak measurement.
Frequently asked questions
Is this an accurate decibel meter?
No — it’s a relative indicator. Browser microphones aren’t calibrated, so treat the reading as a comparison tool, not a certified measurement. A dedicated calibrated meter is needed for accurate SPL.
Is my microphone audio recorded?
No. Everything runs locally in your browser. No audio is stored, uploaded or shared.
Why does the reading differ between my phone and laptop?
Each microphone has different sensitivity and processing, so absolute numbers vary between devices. Use one device consistently when comparing noise levels.
What noise level is harmful?
As a general guide, prolonged exposure above about 85 dB can damage hearing over time, and the risk rises quickly as levels increase. For anything safety-related, rely on a calibrated meter.
Understanding the Limitations of Browser-Based Decibel Meters
While our online decibel meter provides a convenient way to get a sense of your environment’s noise levels, it’s important to recognize its technical limitations:
- Calibration: Browser microphones lack professional calibration, which means the readings are not precise enough for legal, medical, or occupational safety purposes. They are best used for casual comparisons and personal awareness.
- Device Variability: Different devices have varying microphone sensitivities and audio processing capabilities. A reading on a smartphone may differ significantly from that on a laptop, even in the same environment.
- Environmental Factors: Background noise, microphone placement, and even the device’s condition (e.g., a dusty microphone grille) can affect the readings. For the most consistent results, use the tool in a controlled environment.
- Dynamic Range: The tool may not accurately capture extremely low or high decibel levels due to the limited range of consumer device microphones. Very loud sounds might be clipped, while very quiet sounds could be lost in the noise floor.
Tips for Getting the Most Accurate Readings
To maximize the utility of the online decibel meter, consider the following best practices:
- Use a Consistent Device: For comparative measurements, always use the same device in the same location. This minimizes the impact of microphone variability and environmental factors.
- Minimize Background Noise: Try to eliminate as much ambient noise as possible when taking measurements. Close windows, turn off fans, and move away from sources of interference like televisions or radios.
- Calibrate if Possible: While browser microphones cannot be professionally calibrated, you can perform a rough calibration by comparing the meter’s reading to a known noise source. For example, a typical conversation occurs at around 60 dB; use this as a reference point to adjust your expectations of the meter’s accuracy.
- Take Multiple Readings: To account for fluctuations and anomalies, take several readings over a period of time and calculate the average. This will give you a more reliable sense of the average noise level in your environment.
Common mistakes to avoid
- Relying on the Meter for Critical Decisions: Do not use the online decibel meter for decisions that require precise sound pressure level measurements, such as workplace safety assessments or legal disputes. Always use a professionally calibrated device for such purposes.
- Ignoring Environmental Factors: Failing to account for background noise or microphone placement can lead to inaccurate readings. Always consider the environment in which you are taking measurements.
- Assuming All Devices Are Equal: Different devices have different microphones and audio processing capabilities. Do not expect readings from a smartphone to match those from a laptop or tablet.
- Neglecting to Reset the Peak: Forgetting to reset the peak measurement can lead to misleading results. Make sure to reset the peak before taking a new measurement to ensure accurate tracking.
- Overinterpreting the Results: Remember that the readings are relative and not absolute. Use them as a guide rather than a definitive measure of sound levels.
- Not Considering Hearing Safety: Even if the meter is not perfectly accurate, it can still provide a useful indication of potentially harmful noise levels. Use it as a tool to protect your hearing by avoiding prolonged exposure to high decibel levels.
More frequently asked questions
Can I use this tool to measure noise pollution in my neighborhood?
While the online decibel meter can give you a rough idea of noise levels, it is not suitable for measuring noise pollution. For accurate and legally admissible measurements, you would need a professional-grade sound level meter that is calibrated and certified for such purposes.
How can I reduce noise levels in my home?
There are several strategies you can use to reduce noise levels in your home, including installing soundproofing materials, using rugs and curtains to absorb sound, and sealing gaps around doors and windows. Additionally, consider using white noise machines or earplugs to mask or block out unwanted noise.
What are some common sources of harmful noise levels?
Common sources of harmful noise levels include heavy traffic, power tools, concerts, and industrial machinery. Prolonged exposure to these sources can lead to hearing damage over time. It’s important to use hearing protection and limit exposure to such environments whenever possible.