A Pi Attenuator uses a single series resistor, and two shunts to ground (input and output) to attenuate a signal. This calculator lets the user enter in the desired attenuation (in dB) and the system impedance (Zo in Ω’s) and it will calculate the needed shunt resistors (R1) and series resistor (R2).

ATTENUATION (DB)
Value is out of range
IMPEDANCE
Ω
Value is out of range
R 1
Ω
R1 value is out of range
R 2
Ω
R2 value is out of range
FORMULAS
R 1 R 2 R 1