Signal-to-Noise Ratio Calculator

Find the signal-to-noise ratio in decibels.

SNR (ratio) 100

SNR (dB) 20

Formula: SNR(dB) = 10·log₁₀(P_signal ÷ P_noise)

Step-by-step with your numbers:

1. Values used:

2. Signal power = 0.5 W

3. Noise power = 0.005 W

5. SNR = Signal power / Noise power = 0.5 / 0.005 = 100ratio

6. SNR = 20dB

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Signal-to-noise ratio compares the strength of a desired signal to background noise.

The math behind it

As a power ratio it is P_signal ÷ P_noise; in decibels it is 10·log₁₀ of that ratio.

0.5 W signal vs 0.005 W noise → ratio 100 = 20 dB.

Higher or lower is better?

Higher — more signal relative to noise means clearer reception.