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Calculators that show their work.
Calculators for homeowners, DIYers and the trades. Every answer comes with the formula, the assumptions and the code table it came from.
Sheet E
Electrical
Conductor data from NEC 2023 Chapter 9 and Table 310.16.
Sheet C
Carpentry
Stairs and decks checked against the International Residential Code.
Sheet R
Roofing
Pitch conversions and a materials list where every assumption is editable.
General notes
01
Sourced data
Every table value names the code edition and table it came from.
02
Tested math
Formulas are checked against published worked examples before they ship.
03
Visible assumptions
Temperatures, loads and limits are shown and editable, never hidden.
04
Your inspector decides
Codes vary by town and edition. Use these to plan, then confirm locally.