Affiliate Disclosure

Effective 2026-10-15.

ProjectMath participates in affiliate marketing programs. That means we may earn a commission if you click certain product links and make a purchase, at no extra cost to you.

Amazon Associates

ProjectMath is a participant in the Amazon Services LLC Associates Program, an affiliate advertising program designed to provide a means for sites to earn advertising fees by advertising and linking to Amazon.com and affiliated sites. Amazon and the Amazon logo are trademarks of Amazon.com, Inc. or its affiliates.

Product suggestions on calculator and guide pages link to Amazon search or product pages. We do not invent prices on those links; check Amazon for current pricing and availability.

Other retailers

We may also join affiliate programs for home-improvement retailers (for example Home Depot or Lowe’s) when approved. Links from those programs will be disclosed the same way.

Editorial independence

Affiliate partners do not write our cost figures, choose our sources, or approve our calculators. Recommendations are chosen because they match the DIY topic on the page (tools and materials people typically need for that project). We may earn a commission whether or not you buy the exact item you clicked.

How we label links

Near affiliate product lists you will see a short notice such as: “We may earn a commission at no extra cost to you.” This page and the site footer also point here so the disclosure is clear under FTC endorsement guidelines.

Questions: [email protected]

Last reviewed: 2026-10-15. Prices are national planning ranges; get local quotes.