NEC Quick-Reference Tables
Free, field-ready reference values from the National Electrical Code (NEC 2023). Bookmark these pages for fast jobsite lookups — no login required.
- NEC 2023
Table 310.16 — Allowable Ampacities
Copper and aluminum conductor ampacity at 60°C, 75°C, and 90°C temperature ratings. Up to 3 current-carrying conductors in a raceway.
- NEC 2023
Chapter 9, Table 1 — Conduit Fill
Maximum fill percentages for raceways: 53 % for 1 conductor, 31 % for 2, 40 % for 3 or more.
- NEC 2023
Table 314.16(A) — Metal Box Volumes
Cubic-inch volumes for standard device and square outlet boxes used when calculating box fill per NEC Section 314.16.
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