How we research and check our tools
A calculator is only useful if its answer is right. This page explains where our numbers come from, how we test them, and what to do if you find one that is wrong.
Which sources count
Every formula, table and threshold in a tool should trace back to a primary source. In order of preference, that means:
- Published standards and the bodies that maintain them, such as IPC for circuit boards or ASTM for material testing.
- Peer-reviewed papers, when a method comes from research rather than a standard.
- Manufacturer datasheets and technical notes, for figures that depend on a specific product or material.
- Government and university extension pages, for regulations, food safety times and similar guidance.
Forum posts, other calculator sites and encyclopedia articles can point us to a source. They are not the source. When a tool uses a rule of thumb rather than a published method, the page says so.
How a result gets checked
For each tool we collect cases where a source publishes the answer, for example the trace width a standard gives for a set current and temperature rise. We copy the source's exact wording, and a script re-opens the source page to confirm those words are really there. The tool's own code then runs on the same inputs, and its result has to match the published value within a stated tolerance.
When a tool has been through this process, its page shows a "How this was checked" box. It lists each case, the published value, what the tool gives and a link to the source, so you can repeat the check yourself. The box is generated from the same test, so it cannot show a match that the test did not find.
How we use AI
We use AI models to help research topics, draft explanations and write code. AI can state wrong things with confidence, so nothing it produces is published on its word alone. Quotes are matched against the live source, numbers are tested against published values, and any claim that can't be traced back to either is taken out.
We don't list named experts or reviewers, because we don't have a panel of them and won't pretend otherwise. What we offer instead is a method you can follow and results you can check.
What the tools are not
The tools do arithmetic on the numbers you enter, using the methods described on each page. They are not engineering sign-off, medical advice or legal advice. For anything structural, electrical or safety-critical, a qualified professional should confirm the result for your situation.
Corrections
If you think a result is wrong, use the Report a bug button on the tool's page, or email contact@bentoutils.com. Tell us the inputs you used and the answer you expected, and where that answer comes from if you know. When we fix a mistake in a checked tool, the change is listed with its date in that tool's "How this was checked" box.
Tools we have retired
We would rather offer fewer tools that are right than many that are not. In October 2026 we retired tools we could not make clearly better than what already exists, and folded a few into closely related tools. Older tools are being brought up to the standard on this page one at a time.
Your data
Every tool runs in your browser. Your inputs and files are not uploaded to us. See the privacy policy for details.