Editorial Standards

This page explains how a calculator gets published on Pitch & Span, how we handle mistakes, and how the site is monetized.

Before a calculator ships

• Every geometric formula is implemented directly from its mathematical definition and checked against known reference cases with an automated test suite — not eyeballed.
• Every material coefficient and span table value must trace to a named, dated source (a manufacturer spec sheet, a code section, or a trade association publication). If we can't verify one, it isn't published — see Methodology.
• Every worked example on a calculator page is manually cross-checked against the live calculator before publishing, and re-checked after any formula change.

Corrections policy

If a formula, coefficient, or piece of cited data turns out to be wrong, we fix it as soon as we confirm the error, update the page's "Last reviewed" date, and — for anything that would have changed a previously displayed result — note the correction in the "How we checked this page" block. We do not quietly change numbers without a trace.

Found something that looks wrong? Contact us with the calculator, the inputs you used, and what you expected — that's the fastest way to get it checked and fixed.

Review cadence

Pages citing fast-moving data (material costs, in particular) are checked against their source more frequently than pages citing stable geometry or long-lived code references. Every page's own "How we checked this page" block states its specific last-reviewed date.

Monetization disclosure

Pitch & Span is free to use, with no account required. The site may show display advertising and may in the future include affiliate links to tools and materials relevant to a specific calculator (clearly labeled as such, with standard affiliate disclosure, if and when they're added). Advertising placement never appears above a calculator or inside a printed cut sheet, and no calculator's result is influenced by advertiser relationships.

What we don't do

• We don't claim engineering credentials we don't have — see About.
• We don't publish a material coefficient or span value without a citable source.
• We don't accept payment to change a calculator's formula or a published result.

Last reviewed: 2026-07-28.