The meter below shows Leq dB live in Statistics and Advanced panels. Use the full session, not a 3-second snapshot.
What Leq Means
Leq (equivalent continuous sound level) answers: what steady level would carry the same total sound energy as the actual fluctuating sound did over the measured period? It is the energy average:
where each Li is a frame's dB SPL and N is the number of frames. Energy — not decibels — is averaged, then converted back to dB.
This is the metric professionals use for exposure and reporting because it correctly weights loud moments. See the full derivation and the Noise Exposure guide for why Leq is the right input to exposure thinking.
Why Leq Is Different from a Simple Average
Averaging decibels arithmetically is wrong: dB is logarithmic, so a brief loud burst carries far more energy than the arithmetic suggests.
Numeric example:
Three one-second frames: 80 dB, 80 dB, 100 dB.
- Arithmetic mean: (80 + 80 + 100)/3 = 86.7 dB — understates energy.
- Energy average (Leq): 10·log10( (1080/10+1080/10+10100/10)/3 ) = 95.4 dB — correct.
The 100 dB second dominates total energy. Leq reflects that; a plain mean hides it. Our meter corrected to true energy averaging (see Changelog).
Interactive: Leq vs Average
Demonstrates why exposure assessments must use Leq. Try "85, 85, 85" (steady → Leq = mean) vs. "70, 70, 100" (variable → Leq >> mean).
How to Measure Leq Here
- Open the meter; select A-weighting and Fast (or Slow) as desired — Leq integrates raw frames regardless of display smoothing.
- Measure the entire period of interest (e.g. whole commute, full lesson, full task). Leq needs duration to be meaningful.
- Read Leq in Statistics / Advanced Controls. Export CSV/JSON to preserve it, or save to Journal.
- Compare Leq across days/rooms to quantify change; feed Leq + duration into the Exposure Calculator.
FAQ — Leq Meter
What does Leq mean?
How is Leq calculated?
Is Leq the same as average dB?
Related: dBA Meter · dBC Meter · Noise Exposure · Methodology — Leq