How We Verify Our Calculators
A modelling calculator is only useful if the numbers behind it are real. Every figure on this site is traced to a named source: manufacturer product data for track geometry, paints, bases and scenic materials; published game-system conventions and model railway scale standards; and straightforward scale mathematics. This page explains how we check those figures and what we do when one turns out to be wrong.
The process
- ✓Figures are traced to their primary source, not copied from forums: Peco point lengths and frog angles, Games Workshop base sizes, manufacturer thinning ratios from Tamiya, Vallejo, Citadel, Humbrol, AK Interactive and Revell, and scale ratios such as OO 1:76 and N 1:148.
- ✓Every calculator is tested against hand-worked examples with expected answers derived independently from the source, so the code is checked against the maths rather than against itself.
- ✓The whole site went through multi-generation adversarial audits in 2026, where each formula and constant was re-derived from scratch and compared back to the calculator output. Disagreements were fixed in the code, then re-verified.
- ✓Where no manufacturer publishes a coverage rate, such as texture paste or ripple gel per square centimetre, we say so on the page and label the figure as a practical bench estimate you can adjust under Advanced Options.
- ✓Errors reported through the feedback buttons are re-checked against the source, fixed and re-verified before the correction goes live. When a report shows a genuine error, the fix lands on the affected page itself, with a dated correction note where it matters.
- ✓Content is reviewed when sources change: new base size conventions, revised game editions, updated product ranges and current manufacturer datasheets.
Verified, not guaranteed
These calculators give planning estimates, not guarantees. Material quantities vary with your technique, application thickness and the exact products you use, so confirm quantities with your kit instructions and supplier before buying, and check the current rulebook for anything tied to a game system. For adhesives, solvents and airbrushing, always follow the manufacturer’s safety instructions on the product itself.
Spotted an error?
Every calculator page has feedback buttons. If a figure looks wrong, tell us what you entered and what you expected: we investigate against the original source, fix anything that fails the check, and re-verify before the correction goes live.