Sound Level Calculator
Combine decibels and distance loss.
Enter your values
Results update instantly as you type — no submit needed.
Results
- Combined level
- 79.5 dB
- Level at distance
- 61.4 dB
- Loss over distance
- 18.1 dB
- Hearing risk
- Below action level
Quick answer
Decibels add logarithmically — two equal sources give only a 3 dB increase.
L = 10 log10(Σ10^(Li/10))
How to use the Sound Level Calculator
- 1Enter each source level in decibels.
- 2Enter the distance and reference distance.
- 3Check against the 85 dB action level.
Frequently asked questions
Why don't decibels add normally?
The scale is logarithmic — doubling power adds only 3 dB.
How much does distance help?
Each doubling of distance drops free-field level by 6 dB.