dB Gain Calculator

Find gain in decibels from input and output power.

Gain (dB) 20

Formula: gain = 10·log₁₀(P_out ÷ P_in)

Step-by-step with your numbers:

1. Values used:

2. Input power = 0.01 W

3. Output power = 1 W

5. Gain = 20dB

Did we solve your problem today?

Gain in decibels compares output power to input power on a logarithmic scale.

The math behind it

For power, gain = 10·log₁₀(P_out/P_in). Every 10 dB is a tenfold power increase.

0.01 W in, 1 W out → 20 dB gain.

What about voltage gain?

Voltage gain uses 20·log₁₀(V_out/V_in) instead of 10·log.