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Link Budget

Calculate Link Budget instantly with the exact formula and a worked example.

Link Budget

Transmitter powerdBm
Transmit antenna gaindBi
Receive antenna gaindBi
Distancekm
FrequencyMHz
Other losses (cables, connectors, fading)dB
Receiver sensitivitydBm
Link margin
16.95dB
Free-space path loss, line of sightCalculate Link Budget instantly with the exact formula and a worked example.
Free-space path loss
120.05dB
Received power
-73.05dBm
EIRP
35dBm
Rating
Reliable link

More about: Link Budget

What it calculates

The “Link Budget” calculator computes Link margin in dB from 7 parameters: transmitter power (dBm), transmit antenna gain (dBi), receive antenna gain (dBi), distance (km), frequency (MHz), other losses (cables, connectors, fading) (dB), receiver sensitivity (dBm).

A standard physics formula used in educational and engineering tasks.

Example calculation

With parameters Transmitter power = 20 dBm, Transmit antenna gain = 15 dBi, Receive antenna gain = 15 dBi, Distance = 10 km, Frequency = 2,400 MHz, Other losses (cables, connectors, fading) = 3 dB, Receiver sensitivity = -90 dBm the result is 16.95 dB (Free-space path loss, line of sight).

How to use

  1. Enter transmitter power, transmit antenna gain, receive antenna gain, distance, frequency, other losses (cables, connectors, fading) and receiver sensitivity — each field above is adjustable with a slider.
  2. Link margin (dB) is calculated automatically as you type.
  3. Check the worked example below to see the formula applied to real numbers.
  4. Copy the result or bookmark this calculator.

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FAQ

How is Link Budget calculated?
The Link Budget calculator computes Link margin (in dB) from transmitter power, transmit antenna gain, receive antenna gain, distance, frequency, other losses (cables, connectors, fading), receiver sensitivity. Enter your values above and the exact formula is applied instantly; a worked example with real numbers is shown below.
Is the Link Budget calculator free?
Yes. It is completely free, needs no signup, runs entirely in your browser, and sends no data to any server.

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