Decibel (dB)
Calculate Decibel (dB) instantly with the exact formula and a worked example. Free online calculator — no signup, works on mobile.
Decibel (dB)
P1
P2
dB
20
More about: Decibel (dB)
What it calculates
The “Decibel (dB)” calculator computes dB from 2 parameters: p1, p2.
A standard physics formula used in educational and engineering tasks.
Example calculation
With parameters P1 = 100, P2 = 1 the result is 20 (10·log₁₀(P1/P2)).
How to use
- Enter the parameter values — every field above is adjustable with a slider.
- The result and related metrics are calculated automatically as you type.
- Use the additional metrics shown (if any) where needed.
- Copy the result or bookmark the page.