We welcome questions, correction reports, and suggestions for new calculators. Email us at tamsinandrews75+sites@gmail.com and we will respond as quickly as we can.
If you are reporting a calculation concern, please include the inputs you used (length, width, depth, and material) so we can reproduce and verify the result. If you would like to suggest a new material or calculator, tell us about the project type you are planning — the most requested tools get built first.
Writers and publishers: our coverage chart and density tables are free to cite with attribution, and our calculators can be linked directly in your articles.