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Free Space Path Loss Calculator

Calculate signal loss over distance using the FSPL formula

The operating frequency of the wireless link. Common WiFi: 2400 MHz (2.4 GHz), 5200 MHz (5 GHz), 6000 MHz (6 GHz).
The straight-line distance between transmitter and receiver. FSPL assumes clear line-of-sight with no obstacles.
If provided, the calculator will also show the received signal strength after path loss. Leave at 0 to skip.
dBm
Combined antenna gain of transmitter and receiver antennas. Helps calculate received signal level.
dBi total

Path Loss Results

Free Space Path LossdB
Distance (km)km
FrequencyMHz
Received Signal (with antennas)dBm
Wavelengthmm
References: FSPL(dB) = 20*log10(d_km) + 20*log10(f_MHz) + 32.44. Derived from Friis transmission equation. Valid only for free-space (line-of-sight, no reflections/obstacles).