Frequently asked questions
Questions
Are these calculators accurate?
Each one uses the published code table or equation and is tested against the code's own worked examples before it goes live. They are as accurate as those sources, with the limits stated on each page.
Which code editions do you follow?
Electrical calculators use NEC 2017 tables, which are unchanged in the values used here through the 2023 edition. The gas calculator uses the IFGC and NFPA 54 low-pressure sizing equation. Each page names its source.
Do these calculators replace a licensed professional?
No. They are for estimating and checking. Local amendments, the authority having jurisdiction and the conditions on site can all change the answer.
Do you store what I enter?
No. The calculations run in your browser and nothing you type is sent to a server.
Can I suggest a calculator?
Yes. Email [email protected] with the calculation you need and the code section it comes from.