Coax Cable Sizes and Diameter Chart: RG6, RG59, RG11, RG58 and More

Published: June 14, 2026

Coax cable size is usually described by cable type, such as RG6, RG59, RG11, or RG58. Each type has an approximate outer diameter, impedance, flexibility, connector fit, and typical use. If you need the application-level differences first, start with the types of coaxial cable guide. For most home TV and cable internet connections, RG6 is the common size. For long 75-ohm runs, RG11 is larger and lower loss. For RF, radio, and test equipment, 50-ohm coax types such as RG58, RG8, RG213, and RG174 are common.

Coax Cable Diameter Chart

Cable Type	Approx. Outer Diameter	Impedance	Typical Use
RG174	2.5 mm / 0.10 in	50 ohm	Small RF pigtails, compact antenna leads
RG58	5.0 mm / 0.20 in	50 ohm	RF, radio, short test cables
RG59	6.1 mm / 0.24 in	75 ohm	Older video, CCTV, short analog runs
RG6	6.9 mm / 0.27 in	75 ohm	TV, cable internet, satellite, antenna
RG8	10.3 mm / 0.40 in	50 ohm	RF transmission, radio
RG11	10.3 mm / 0.40 in	75 ohm	Long cable TV, satellite, broadband runs
RG213	10.3 mm / 0.40 in	50 ohm	RF transmission, antenna feed lines

These sizes are approximate. Actual diameter can vary by manufacturer, jacket material, shielding, plenum rating, and outdoor or direct-burial construction.

Important Accuracy Note

Coax cable diameter charts should be treated as approximate selection guides, not final engineering specifications. The same broad cable family can have different outside diameters depending on:

Variable	How It Changes Cable Size
Shield count	Quad-shield cable is often larger than standard shielded cable
Jacket rating	Plenum, riser, outdoor, and direct-burial jackets can differ
Manufacturer	Commercial RG labels do not guarantee identical construction
Connector system	Compression, crimp, and clamp connectors may require exact cable dimensions
Conductor type	Solid, stranded, copper, and copper-clad steel designs may differ

For connector selection, use the cable manufacturer's datasheet rather than only a general chart.

How Coaxial Cable Sizes Are Measured

Coaxial cable size usually refers to the outside diameter of the finished cable, including the outer jacket. This matters because it affects:

Connector compatibility
Bend radius
Cable routing
Pulling through walls or conduit
Signal loss over distance
Flexibility

The center conductor size, dielectric, shield, and jacket also matter, but the outside diameter is the easiest physical size to compare.

RG6 Diameter

RG6 coaxial cable is about 6.9 mm or 0.27 in in outer diameter, depending on construction. It is the standard size for most modern home TV, satellite, antenna, and cable modem connections. For TV-specific installation choices, see the best coaxial cable for TV article.

RG6 Feature	Detail
Approx. diameter	6.9 mm / 0.27 in
Impedance	75 ohm
Common connector	F-type
Common use	TV, satellite, antenna, cable internet

Quad-shield RG6 may be slightly larger than standard RG6 and requires compatible connectors.

RG59 Diameter

RG59 coaxial cable is about 6.1 mm or 0.24 in in outer diameter. It is slightly thinner than RG6 and is often found in older video and CCTV installations.

RG59 Feature	Detail
Approx. diameter	6.1 mm / 0.24 in
Impedance	75 ohm
Common connector	BNC, RCA, F-type
Common use	Older analog video, CCTV

RG59 is easier to bend than RG6, but it is usually not preferred for modern high-frequency TV, satellite, or cable internet runs.

RG11 Diameter

RG11 coaxial cable is about 10.3 mm or 0.40 in in outer diameter. It is much thicker than RG6 and is used for long 75-ohm cable runs.

RG11 Feature	Detail
Approx. diameter	10.3 mm / 0.40 in
Impedance	75 ohm
Common connector	F-type
Common use	Long cable TV, satellite, broadband, outdoor runs

RG11 has lower signal loss over long distances, but it is harder to route and bend.

RG58 Diameter

RG58 coaxial cable is about 5.0 mm or 0.20 in in outer diameter. It is a common 50-ohm cable for RF, radio, and short test leads.

RG58 Feature	Detail
Approx. diameter	5.0 mm / 0.20 in
Impedance	50 ohm
Common connector	BNC, SMA, N-type, UHF
Common use	Short RF and radio connections

RG58 is flexible and convenient, but larger 50-ohm cables are better for longer or lower-loss RF runs.

RG174 Diameter

RG174 is much smaller than RG58, at about 2.5 mm or 0.10 in. It is used for short RF pigtails and compact internal connections. The advantage is flexibility and small size. The disadvantage is higher loss, especially at higher frequencies.

Does Cable Diameter Affect Signal Quality?

Cable diameter can affect signal quality indirectly. Larger coaxial cables often have lower attenuation than smaller cables of the same general category, especially over longer distances and higher frequencies. However, diameter is not the only factor. Signal performance also depends on:

Factor	Why It Matters
Impedance	Must match the system, usually 50 ohm or 75 ohm
Shielding	Reduces interference and signal leakage
Conductor material	Affects resistance and performance
Dielectric	Affects impedance and loss
Frequency	Higher frequencies usually have more loss
Cable length	Longer runs lose more signal
Connector quality	Poor connectors can cause loss or reflections

A larger cable is not automatically better for every use. It must match the equipment and installation.

Coax Cable Size vs Signal Loss

In general, longer cable runs and higher frequencies need lower-loss cable. That is why RG11 is often used instead of RG6 for long 75-ohm runs, and why larger 50-ohm RF coax may be used instead of RG58 for long antenna feed lines.

Situation	Better Cable Choice
Short TV patch cable	RG6
Long TV or satellite run	RG11
Short RF test lead	RG58
Longer RF antenna feed	RG8, RG213, or another lower-loss 50-ohm coax
Compact internal RF lead	RG174

Which Coax Size Should You Choose?

Need	Recommended Size
Home TV or cable modem	RG6
Outdoor antenna run	RG6, or RG11 for long runs
Long cable TV distribution	RG11
Older CCTV or analog video	RG59
Short RF test cable	RG58
Long RF antenna cable	RG8, RG213, or other low-loss 50-ohm coax
Small internal antenna cable	RG174

When in doubt, start with the equipment requirements. The correct impedance and connector type are more important than diameter alone. If you are identifying a loose cable before measuring it, use the guide on what a coax cable looks like.

Connector Fit Checklist

Cable diameter matters most when you are choosing connectors. Before buying connectors for bulk coax, check:

Cable family, such as RG6, RG59, RG11, or RG58
Outside jacket diameter
Dielectric diameter
Center conductor diameter
Shield type and shield count
Connector style: compression, crimp, solder, clamp, or twist-on
Indoor, outdoor, or weather-sealed requirement

This is especially important for quad-shield RG6 and RG11 because they may not fit connectors intended for standard RG6.

FAQ

What size is RG6 coax cable?

RG6 coaxial cable is typically about 6.9 mm or 0.27 in in outer diameter, but exact size varies by manufacturer and construction.

What size is RG59 coax cable?

RG59 is typically about 6.1 mm or 0.24 in in outer diameter.

What size is RG11 coax cable?

RG11 is typically about 10.3 mm or 0.40 in in outer diameter.

What size is RG58 coax cable?

RG58 is typically about 5.0 mm or 0.20 in in outer diameter.

Is RG11 bigger than RG6?

Yes. RG11 is significantly thicker than RG6 and is usually used for longer runs where lower loss is needed.

Does thicker coax cable mean better signal?

Not always. Thicker coax often has lower loss over distance, but the cable must still match the system impedance, connector type, frequency, and installation needs.

Are coax cable sizes exact?

No. Published diameters are usually approximate. Jacket type, shielding, rating, and manufacturer design can change the actual size.

For usage recommendations by TV, internet, and Ethernet adapter scenarios, see the full Coaxial Cable Guide. For modem, router, and MoCA use cases, see coaxial cable vs Ethernet cable.

About the Author

MOZ Official Authors

The MOZ Electronics engineering team publishes practical guides on electronic components, connector standards, wireless modules, and procurement best practices for engineers and buyers worldwide.