Sound Intensity Calculator
Calculate sound intensity level (dB) from acoustic power and area, or convert between intensity (W/m²) and dB SPL.
Use the Sound Intensity Calculator
Sound Intensity Calculator
Total acoustic power output of the source
Distance from the point source
Result
Enter values and click Calculate
Level on dB scale (0–194 dB)
0 dB (Threshold)
120 dB (Pain)
194 dB (Max)
Common Sound Levels
| Source | dB SPL | Intensity (W/m²) |
|---|---|---|
| Threshold of hearing | 0 | 1.0×10⁻¹² |
| Rustling leaves | 20 | 1.0×10⁻¹⁰ |
| Quiet library | 40 | 1.0×10⁻⁸ |
| Normal conversation | 60 | 1.0×10⁻⁶ |
| Busy traffic | 80 | 1.0×10⁻⁴ |
| Lawn mower | 90 | 1.0×10⁻³ |
| Rock concert | 110 | 1.0×10⁻¹ |
| Threshold of pain | 120–130 | 1–10 |
| Jet engine (30 m) | 150 | 1.0×10³ |
Summary
Sound intensity describes how much acoustic power passes through a unit area. This calculator lets you compute the sound intensity level in decibels (dB SPL) from acoustic power and distance, or directly convert between intensity in watts per square meter (W/m²) and dB SPL. It uses the standard reference intensity of 1×10⁻¹² W/m², the threshold of human hearing.
How it works
- Choose a calculation mode: Power → dB, Intensity → dB, or dB → Intensity.
- Enter the required values (power in watts, distance in meters, or intensity in W/m²).
- Click Calculate to see the result instantly.
- Use the reference table to compare your result with common sound levels.
- Results are computed using the standard formula: L = 10 × log₁₀(I / I₀).
Use cases
- Estimate dB levels from a speaker or loudspeaker at a given distance.
- Check whether a work environment exceeds safe noise exposure limits.
- Convert measured intensity readings to dB SPL for comparison.
- Understand how sound level drops with distance (inverse-square law).
- Study acoustic physics for exams or professional certifications.
- Verify engineering calculations for noise control projects.
Frequently Asked Questions
Last updated: 2026-05-23 · Reviewed by Nham Vu