HFC Coax Signal Loss Calculator

Estimate coax attenuation from cable type, frequency, and cable length.

Cable loss
—
dB
Attenuation
—
dB / 100 ft
Ending level
—
dBmV
How the calculator works

The attenuation tables contain manufacturer-published loss values at specific frequencies. For a frequency between two published points, the calculator linearly interpolates the loss rate, then scales it to the entered cable length.

Total loss (dB) = attenuation (dB/100 ft) × length (ft) ÷ 100

The result is cable attenuation only. It does not include taps, splitters, directional couplers, connectors, splices, equalizers, amplifiers, or other plant devices.

Reference data in this version is based primarily on CommScope drop-cable and P3 hardline attenuation tables at 68°F / 20°C. Actual cable loss can vary by manufacturer, construction, age, and temperature.