Signal-to-Noise ratio calculator

The dB rule is the part people get wrong: a voltage ratio goes through 20 log, a power ratio through 10 log, and two dBm readings subtract directly. SINAD is noise and distortion added as powers, never as decibels. ENOB comes from the ideal-converter identity SNR = 6.02 x ENOB + 1.76, so it counts quantization noise only: flicker noise, burst noise, and drift are outside its reach. The kTB floor is physics, and -174 dBm/Hz at room temperature is where it starts; narrowing the bandwidth is the only way to sit lower, and the noise figure tells you how far above physics your receiver actually lives.