Link Budget Calculator
Plan point-to-point and PtMP wireless links with confidence. Compute EIRP, free-space path loss and expected receive signal in real time.
Global Link Parameters
Common: 2400, 5180–5825, 24000, 60000
A Site A Access Point · Tx
B Site B Station · Rx
Expected Rx Level
excellent- Total EIRP (Site A)
- 46 dBm
- Free Space Loss
- 121.69 dB
- Total Antenna Gain
- 38 dBi
Run your whole WISP, not just the math.
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Understanding Link Budgets
A link budget accounts for all of the gains and losses from the transmitter, through the medium (free space, cable, waveguides, fiber, etc.) to the receiver in a telecommunication system.
The Formula
Rx = Tx + Tx Gain − Tx Loss − FSPL + Rx Gain − Rx Loss
EIRP
Equivalent Isotropically Radiated Power — the power a theoretical isotropic antenna would emit to match the peak density in the direction of maximum antenna gain.
Why use the ISPbox Calculator?
Our Free Link Budget Calculator is designed for Wireless ISPs (WISPs) who need a quick, accurate alternative to complex vendor tools like Ubiquiti AirLink, Mikrotik Link Calculator, or Mimosa Design Tool.
- Vendor Neutral: Works with any hardware (Ubiquiti airFiber, Mimosa B5, Mikrotik NetMetal, Cambium PTP).
- Multi-Frequency: Supports 2.4 GHz, 5 GHz, 24 GHz, and 60 GHz bands.
- Professional Metrics: Calculates Free Space Path Loss (FSPL) and System Operating Margin.
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