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Conduit Fill Calculator

Build a cable bundle and check NEC Chapter 9 compliance with visual cross-section and size recommendations.

Build Your Cable Bundle

Video

HDMI (Standard)(0.3" OD)
0
HDMI (Slim/High-Speed)(0.22" OD)
0
RG6 Coax(0.332" OD)
0
Fiber HDMI(0.2" OD)
0

Network

Cat6 Ethernet(0.25" OD)
0
Cat6a Ethernet(0.3" OD)
0

Audio

14 AWG Speaker Wire(0.26" OD)
0
16 AWG Speaker Wire(0.21" OD)
0
12 AWG Speaker Wire(0.33" OD)
0
Subwoofer/RCA Cable(0.25" OD)
0

Data

USB-C Cable(0.18" OD)
0

Control

IR Emitter Cable(0.12" OD)
0

Conduit Fill

0%

Add cables to see fill

NEC Compliant

NEC max for 0 cables: 40%

Conduit Cross-Section

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Video Network Audio Data

Fill Percentage

0%NEC Limit (40%)100%

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Conduit Fill for AV Installations

Running AV cables through conduit is best practice for clean, professional installations. The NEC Chapter 9 sets fill limits: 53% for one cable, 31% for two, and 40% for three or more. Overfilling makes pulling difficult and can damage cables.

Plan for future expansion — size conduit so it's only 30% full initially. Pair with our Speaker Wire Gauge Calculator and Voltage Drop Calculator.

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