Antenna Gain Beamwidth Calculator

May 11, 2026

Antenna Gain Beamwidth Calculator

Estimate realized gain, azimuth beamwidth, elevation beamwidth, and far-field distance for dishes, panels, yagis, horns, and more.

📶Preset Scenarios

Antenna family Select the antenna model that matches the physical geometry. Frequency

Use the center frequency or operating channel. Dimension units

Linear sizes update when you switch units. Panel width Use the largest physical span or aperture width. Panel height Use the matching height or family-specific count. Aperture efficiency (%) Includes illumination and construction efficiency. Taper or spillover loss (dB) Higher taper usually smooths sidelobes but trims gain. Feedline loss (dB) Add coax, connectors, and short jumper losses here. Polarization mismatch (dB) Use this for skew, cross-pol, or rotation penalty. Pointing error (deg) Narrow beams lose more gain from small aim errors.

Realized Gain

0.0

dBi

Azimuth HPBW

0.0

deg

Elevation HPBW

0.0

deg

Far-Field Start

0.0

Full Breakdown

Wavelength

0.00 cm

from center frequency

Capture Area

0.00 cm²

physical or equivalent

Effective Aperture

0.00 cm²

derived from realized gain

Beam Solid Angle

0.000 sr

smaller means tighter beam

🧬Antenna Family Reference

Family	Gain model	Beamwidth model	Best use
Parabolic dish	4πA/λ²	70λ/D	Long point links
Panel / horn / sector	4πA/λ²	58λ/W,H	Campus or AP use
Yagi	Empirical	155/√G	Directional receive
Collinear / helix	Empirical	Az 360 / El model	Omni or circular

Band	Wavelength	Common antenna	Typical fit
433 MHz	69 cm	Collinear	Garage links
900 MHz	33 cm	Yagi	Rural telemetry
2.4 GHz	12.5 cm	Panel	Mesh backhaul
5.8 GHz	5.2 cm	Dish	Bridge links

Loss input	Typical range	Effect	Note
Taper loss	0.5-2 dB	Lowers gain	Tames sidelobes
Feedline loss	0.2-3 dB	Direct subtraction	Coax and pigtails
Pol mismatch	0-3 dB	Cross-pol penalty	Check rotation
Pointing error	0-5 dB	Depends on beam	Narrow beams hurt

Preset	Type	Gain goal	Beam goal
2.4 GHz rooftop	Panel	14 dBi	30 deg
5.8 GHz bridge	Dish	29 dBi	5 deg
900 MHz yagi	Yagi	11 dBi	45 deg
3.5 GHz sector	Sector	17 dBi	20 deg

Tip: Use f/D to tune dish illumination.

Tip: Beamwidth shrinks as aperture grows.

Tip: Pointing error hurts narrow beams.

Tip: Subtract feed loss after gain math.

Realized gain is the modeled antenna gain after efficiency, taper, feedline, polarization, and pointing losses are applied to the same geometry.

Antenna gain and antenna beamwidth are two related properties of an antenna. Antenna gain and antenna beamwidth dictate how the antenna distribute the signals in the surrounding space. Antenna gain describe how focused the energy radiated from the antenna is; the more higher the antenna gain, the more focused the energy.

Antenna beamwidth, which is the width of a cone containing the strongest signal radiated from the antenna, describes the range of angles within which the antenna can radiate its signal. Antennas with higher gain has narrower beamwidths. Antennas with narrow beamwidths have their signal focused into a smaller portion of the surrounding space.

How Antenna Gain and Beamwidth Work

If the narrow beam of an antenna is aimed incorrect, the signal strength will drop. Antennas with wide beamwidths allow the antenna to be less precise with the direction of the antenna, but have lower gain. The relationship between antenna gain and antenna beamwidth is related to the physical size of the antenna.

As the physical size of the antenna increase, so does the antenna gain. For instance, if a parabolic dish antenna is twice as wide than another parabolic dish antenna, the wider antenna will have more gain and a narrower beamwidth. The wider antenna will have more gain because it has more surface area to reflect the signal, but it will have a narrower beamwidth because the signal is reflected from a larger surface area and is therefore more focused.

Thus, antenna gain and antenna beamwidth are inversely related to one another; as one increases, the other decrease. Many factor can lead to signal loss from an antenna installation. Antenna pointing error can cause signal loss; however, the effect of antenna pointing errors is more detrimental on antennas with narrow beamwidths.

Polarization skew can also cause signal loss, which occur when the transmitting and receiving antennas dont have the same plane of polarization. Signal loss can also occur along the coaxial cable that connect the antenna to the radio transmitter and receiver, as well as due to the way in which the signal illuminates the antenna’s surface area. Each of these factors will reduce the actual gain that the antenna can achieve, as compared to the theoretical antenna gain.

The beamwidth of the antenna that should be selected depends upon the needs of the wireless network that is to be created. For point-to-point links between two locations, one should of use an antenna with high gain and narrow beamwidth. For links between a wireless access point to many wireless devices, one should use an antenna with lower gain and high beamwidth.

Many antenna installation professional make the mistake of selecting an antenna with the highest possible gain. High gain antennas has narrow beamwidths, which may be more difficult to aim correctly. Finally, the frequency at which the antenna will operate will also affect the gain and beamwidth of the antenna.