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SNR calculator dBm

Use this tool to calculate the SNR from Signal and Noise power values expressed in dBm.

Formula

SNR (dB) = Signal power (dBm) – Noise power (dBm)

Example SNR Calculation

For a Signal power of 10 dBm and Noise power of 3 dBm, the resulting SNR is 7 dB.

Signal and Noise Power Calculation

Noise power can be calculated using either:

kTB noise calculator
V_RMS to dBm calculator
V_peak-to-peak to dBm calculator

Signal power can also be calculated using the same V_RMS or V_peak-to-peak to dBm calculators