NEC Conduit Fill Calculator (Chapter 9)
How many wires can I put in a 1/2-inch conduit?
It depends on wire size and type. Per NEC Chapter 9, 1/2-inch EMT holds up to nine 14 AWG THHN, six 12 AWG THHN, or four 10 AWG THHN at the 40% fill limit for three or more conductors. Larger conductors fill it fast — only two 8 AWG THHN fit. Always count by cross-sectional area, not just wire quantity.
Run the numbers for your project
Use the NEC Conduit Fill Calculator (Chapter 9) to get an exact answer for your inputs.
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