The following straight-forward formulas are employed to calculate losses across an optical fiber link: Total Link Loss = Connector Loss + Cable Attenuation + Splice Loss Cable Attenuation (dB) = Length (km) x Attenuation Coefficient (dB/km)The following straight-forward formulas are employed to calculate losses across an optical fiber link: Total Link Loss = Connector Loss + Cable Attenuation + Splice Loss Cable Attenuation (dB) = Length (km) x Attenuation Coefficient (dB/km)Corning's link loss budget calculator will calculate your total link loss and tell you if your system falls within Corning's recommended guidelines. The power budget refers to the amount of fiber optic cable plant loss that a datalink (transmitter to receiver) can tolerate in order to operate properly. Sometimes the power budget has both a minimum and maximum value, which means it needs at least a minimum value of loss so that it does not. To ensure a fiber optic link operates correctly, you need to calculate its loss, power budget, and power margin. The calculation methods are as follows. Fiber optic loss calculation formula:. Design and validate fiber-optic links in seconds. First, you should be aware of the fiber loss formula: The Total Link Loss = Cable. The calculation of the fiber loss factor is straightforward—simply multiply the loss factor by the total length of the fiber optic cable.