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    Low-Voltage Conduit Fill Calculator (%)

    Why are low-voltage cables sized by outer diameter?

    Data and communications cables (Cat 5e/6/6A, coax, fiber) are rated by finished outer diameter, not by an AWG conductor-plus-insulation pairing like power conductors. The calculator computes each cable's cross-section from its nominal OD, so confirm those diameters against the manufacturer's cut sheet before trusting a tight fill.

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    Use the Low-Voltage Conduit Fill Calculator (%) to get an exact answer for your inputs.

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    Related questions

    Estimates and general guidance only. Verify against your local code and AHJ before any installation. Gas, electrical, and refrigerant work is hazardous to untrained users.

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