Pi Attenuator Resistor Calculator
Calculate equal-impedance resistive pi-pad values and transmitted power fraction for entered attenuation.
YOUR CALCULATION
Result
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Calculation steps
Work through one step at a time or reveal the complete calculation. The steps use your current inputs.
How to calculate
Use a symmetric resistive pi network with one shunt at each port and one resistor in series between the ports.
K=10^(dB/20); each shunt=R0(K+1)/(K−1); series=R0(K²−1)/(2K)
Worked example
For 50 Ω and 6 dB attenuation, each shunt is about 150.476024 Ω and the series resistor about 37.351877 Ω.
Assumptions and input details
Equal real matched terminations and ideal frequency-independent resistors. Attenuation is insertion loss under matching, not unloaded divider gain. Parasitics and resistor power ratings are excluded.
Unit definitions
Unit selection is independent of language. Each selector contains only units for its physical quantity. Calculations use defined base units internally.
SI prefixes are explicit: for example, milli means one thousandth, micro one millionth and kilo one thousand. Changing a unit changes the interpretation of the entered number.
Using this calculator
Can I enter my own problem?
Yes. Replace the example values with your own inputs. The result, calculation steps, tables and applicable diagrams update from those inputs. Blank or invalid values clear the result; example values are never silently substituted for missing inputs.
Are the results exact?
Results use floating-point arithmetic and displayed rounding. Read the formula, assumptions and any stated data precision before interpreting the result.
Is my input uploaded?
The calculation runs in your browser. No account, file upload or external AI service is required. Inputs are not saved between page reloads.
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