How We Research

What we do

1. Start with real demand. We pick topics from questions people actually search for and ask on forums.
2. Shortlist real products. Every product links to a live Amazon.com listing that we opened and checked on the date shown in each guide.
3. Use primary sources for specs. We take specs from the manufacturer's website or the product's Amazon.com listing, and we say which. When a figure is only the maker's claim (for example peak amps or "fills a tire in X seconds"), we label it.
4. Read independent testing. Where respected testers have published results, we link to them so you can see their data.
5. Explain who each product is for. We'd rather tell you which size you need than crown one "winner" for everyone.
6. Update. Each guide shows a Last updated date. We recheck links and specs when we update.

What we don't do

• We don't claim hands-on testing we haven't done. If we test products ourselves in future, we'll say so in that guide.
• We don't publish star ratings, scores or reviews we didn't create, and we don't copy customer reviews.
• We don't list prices. Amazon prices change constantly, so we link to the listing ("Check price on Amazon").
• Brands can't pay to be included or ranked.

How we make money

We earn a commission when you buy through some of our links, at no extra cost to you. See our affiliate disclosure. Commissions never decide which products we include.

Questions or corrections? See Contact.