VoltLab is a small collection of free, no-signup, ad-supported online calculators for power and electrical engineering professionals. Our tools are designed to give you a quick first-pass answer — never a substitute for a formal engineering study, but useful when you need a sanity check at 11 p.m. with a deadline in the morning.
Most online engineering calculators fall into one of two camps: (a) ad-laden single-page apps with broken formulas, or (b) heavy enterprise software that costs $200/month. VoltLab aims for the middle: correct formulas, cited standards, no login, no tracking, no data collection. Each tool cites the relevant IEEE, IEC, or NEC clause so you can defend the result in your own report.
VoltLab is maintained by TaoXue_Dragon — a practicing electrical engineer with 10+ years of experience in power-system integration, substation automation, and protection coordination. The tools reflect formulas the author has actually used on the job, not generic textbook snippets scraped from the web.
This site is supported by Google AdSense. We do not sell user data, run analytics scripts, or place tracking cookies. We do not accept sponsored placements that would compromise the neutrality of our calculations. Ads are served based on page context only.
Please contact us with the calculator name, inputs, expected output, and a citation. We will fix it and credit the correction.