NEC Tables
Every NEC table the calculators draw from, rendered from one shared data file
(js/nec-data.js) — what you see here is exactly what the calculators use.
Search by title or NEC reference, filter by category, or jump straight to a table.
Cells shown as — are intentionally omitted from the audited data set; read the printed Code for those.
Edition: values are identical in the 2020 and 2023 NEC; only Article 220 section/table
numbers were reorganized in 2023, shown as dual labels (e.g. 2020 Table 220.42 / 2023 Table 220.45).
2020 numbers govern the PE exam; 2023 numbers govern current design.
No tables match — clear the search or pick another category.
Study tool — not for design.
Values are on a 2020 NEC (NFPA 70-2020) basis for PE Power exam prep, and were verified against the
2023 NEC on 2026-06-15 — all values match; only Article 220 section numbers moved (dual-labeled).
Screening only, NOT for stamped design. Verify every value against the printed Code (2020 for the exam,
2023 for current design) — and any table notes flagged "verify" above — before relying on it.