Link Budget Calculator
Calculate received signal power and link margin for any wireless system using free-space path loss.
Frequently Asked Questions
What is a link budget?
A link budget is a calculation of all the gains and losses in a radio transmission system, from the transmitter through the propagation medium to the receiver. It determines whether a reliable radio link can be established between two points.
What is a good link margin?
A positive link margin means the received signal exceeds the receiver sensitivity. Most systems design for a margin of 10–20 dB to account for fading, interference, and varying conditions. A margin below 0 dB means the link will not work under the modeled conditions.
Does this account for multipath or shadowing?
No — this calculator uses free-space path loss only, which is the theoretical minimum path loss. Real-world environments add shadowing (typically 8–10 dB standard deviation in urban areas) and multipath fading on top of FSPL. The "Additional Losses" field can be used to account for these factors.