Tell us what needs attention.

For calculation problems

Please include the page address, selected units, all entered dimensions, the result shown and the result you expected. Do not include purchase-order numbers, customer names, shipment references or other confidential information.

For content corrections

Identify the exact sentence or table row and, where possible, include a link to a specific standards, government, manufacturer or carrier source that supports the correction.

For privacy requests

Use the subject “Privacy request” and explain whether you are asking for access, correction or deletion. Calculator inputs are normally processed in your browser, so we may not hold data that identifies a calculation unless you emailed it to us.