Wiring is bought by part number far more often than by conductor size, which is how two cables that look identical from the outside end up behaving differently. The gauge is one of the few properties you can read off a jacket legend and verify with a caliper, which makes it worth understanding.
Figure 1: Comparison of 23 AWG vs 24 AWG solid copper conductor cross-sections.Quick answer
Question | Answer |
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Typical Cat6 conductor | 23 AWG |
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Typical Cat5e conductor | 24 AWG |
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Range permitted in Cat6 constructions | Roughly 22 to 26 AWG, depending on construction and shielding |
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Solid or stranded | Solid for permanent links; stranded for patch leads |
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Conductor material assumed by the category | Solid bare copper |
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Thin patch leads | Often 28 AWG stranded, and a different product from a horizontal cable |
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What AWG means, and why the numbers run backwards
AWG is American Wire Gauge, and the numbering is inverted: a smaller number is a thicker conductor. 23 AWG is thicker than 24 AWG, and 28 AWG — the gauge used in slim patch leads — is much thinner than either.
For a rough sense of scale, 23 AWG is roughly 0.573 mm in diameter and 24 AWG roughly 0.511 mm. The difference looks trivial in a drawing and shows up clearly in the electrical measurements, because resistance and attenuation both track cross-sectional area.
Why Cat6 moved to a thicker conductor
The step from 24 AWG to 23 AWG is small in absolute terms and is one of the two changes that let Cat6 reach 250 MHz where Cat5e stops at 100 MHz.
Higher frequencies attenuate faster in a conductor. Moving to a slightly larger one reduces the loss per unit length, which buys back some of the budget that the wider frequency range consumes. It works alongside the spline — the separator that holds the four pairs apart — and together the two changes are what the extra 150 MHz is made of.
Thicker copper also means a stiffer, heavier cable. That has consequences for the pathway: more force to pull, a larger bend radius, and fuller conduit for the same pair count.
Solid against stranded
These are two different products and they are not substitutes.
Solid conductor is a single copper core per wire. It is used for permanent links because it has lower attenuation, punches down reliably into insulation-displacement terminals, and holds its position once terminated. It is also the one that does not tolerate repeated flexing — bend a solid conductor enough times and it fatigues and breaks.
Stranded conductor is a bundle of fine wires. It is flexible and it is what patch leads are made from, because a lead gets plugged and unplugged thousands of times and routed around a desk. Its attenuation is slightly higher than solid, which is one reason patch cordage is limited to 10 meters within the channel.
Some Cat6 constructions are offered with a stranded center conductor for permanent links, usually for ease of pulling. If the permanent link is stranded, the installation has given away some of the electrical advantage the category was specified to deliver.
The thin patch lead, and what it costs
Slim patch leads at 28 AWG have become common because they help with airflow in a crowded rack and make cable management less painful. They are a legitimate product, and they are not the same thing as a standard patch lead.
The thinner conductor attenuates more, so the cordage budget is consumed faster. Keep thin leads short, keep them out of channels that are already close to their limits, and do not use them as a substitute for a proper horizontal run because they are easier to route. A 10-meter 28 AWG lead at both ends of a channel planned around standard cords is a measurable loss of margin.
Where the gauge shows up in the field
- Pull tension. Thicker copper plus more insulation means a heavier cable and a lower safe pulling tension. The limit is set by the cable, not by what the crew finds comfortable.
- Bend radius. A stiffer cable takes a wider minimum bend. Four times the outer diameter is the number to design to.
- Punch-down. 23 AWG seats well in a jack designed for it. Forcing it into a terminal sized for 24 AWG, or the reverse, is how intermittent contacts are made.
- Conduit fill. Thicker cable means fewer cables in the same conduit, which matters when a pathway is already tight and someone adds drops later.
- Weight. A 305-meter reel of 23 AWG cable is heavier than the same length at 24 AWG, which matters on long pulls and on the structural rating of trays.
About that thinner number on the box
Some cable is sold with a gauge figure that describes the overall core while the actual conductor inside is a copper-clad aluminum or reduced-copper construction. The category specification assumes solid copper, and a clad conductor does not behave like one at these frequencies. If the price is far below everything else on the page, check the conductor construction rather than the gauge number.
Field scenarios
A contractor comparing two Cat6 reels at very different prices. Compare the conductor construction and the gauge, not just the category. Same category, different copper, different result.
A rack being tidied with 28 AWG leads throughout. Fine for short runs between adjacent units. Check the channel budget before using them on a long desk run.
A long pull through a filled conduit. 23 AWG is stiffer and larger than 24 AWG. Verify the fill calculation and the fill percentage before ordering, and consider whether the pathway needs to be re-planned rather than the cable re-specified.
FAQ
Is Cat6 23 or 24 AWG?
23 AWG is typical. Cat5e is typically 24 AWG. Cat6 constructions are permitted over a range, so the jacket legend is the authority.
Does gauge affect speed?
Not directly. It affects attenuation, which affects how much of the channel’s frequency range can be used at length — and that is what limits the achievable rate over distance.
Can I use Cat5e connectors on 23 AWG Cat6 cable?
Physically they may fit, but the connector is rated for the category it was designed for. Match the component rating to the channel rating.
Are thin Cat6 cables as good as standard ones?
For short patch runs, yes. For anything approaching the channel length limits, the thinner conductor costs you margin.
Is stranded Cat6 cable acceptable for permanent links?
It works electrically at short distances, but solid conductor is what the permanent-link installation is designed around and what certifies most reliably.
What about copper-clad aluminum?
It is a different conductor and it does not meet the category’s assumptions about performance. Treat a CCA listing as a different product, not a cheaper version of the same one.
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