Download your PDF
Sound Level Distance Attenuation Calculator result sheet — free, supported by sponsors. Your download button appears in 20 seconds.
This free download is supported by sponsors — continuing in
20
Your file is generated in your browser when you choose Download — nothing is uploaded. If this calculator returns enough numeric data, the export also includes its best-fit chart alongside the readable table.
WorldCalculate result export
Sound Level Distance Attenuation Calculator — result sheet
Estimate free-field sound-level change when the distance from a point source changes.
Inputs used
Results
Visual chart
Breakdown
Calculation steps
Returned data table
Formula and methodology
Formula: L₂ = L₁ − 20 log₁₀(r₂/r₁); intensity ratio = (r₁/r₂)².
For a point source in a free field, the calculator applies inverse-square spreading to estimate the level at a second distance and reports the loss and relative intensity.
This result follows the calculator's declared inputs, precision, validation boundaries, and model limits.
Input contract
- Level at reference distance — dB; minimum -200; maximum 300
- Reference distance — m; minimum 1.0E-6; maximum 1000000000
- Target distance — m; minimum 1.0E-6; maximum 1000000000
Worked example
| Input | Value |
|---|---|
| Level at reference distance | 90 |
| Reference distance | 1 |
| Target distance | 4 |
The estimated level at 4 m is 77.96 dB, a 12.04 dB loss.
Assumptions and limits
- The source is approximated as a point source radiating uniformly in a free field with no reflecting boundaries.
- The entered level uses the same measurement convention at both distances and atmospheric absorption, frequency weighting, wind, and barriers are not modeled.
- The estimate is not an occupational exposure decision or a substitute for a measured site survey.
Calculator note
Source and methodology
Use the official WorldCalculate methodology policy for the source, formula, precision, and boundary standards behind this calculator.
Planning estimate, not financial, medical, legal, or professional advice. © WorldCalculate — reuse with attribution. Built and curated by Hassan ALRowaie.
No saved result was found. Please run the calculation first, then choose Download again.