Privacy policy

Last updated: November 6, 2026

Who we are

Watt & Wrench (wattandwrench.com) publishes guides, parts lists and free calculators for home power projects. Questions about this policy, or about data we hold about you, go to hello@wattandwrench.com.

What we collect and how

• Your email address, if you sign up. The signup form sends your address, the page you signed up from, which offer you chose, and the time. Cloudflare holds that record until our system next collects it. We then add your address to our mailing list, keep a note on our own computer that it was added (so it is never added twice), and delete the record from Cloudflare. If you sign up a second time with an address we already have, that second record can stay at Cloudflare until we clear it.
• Clicks on product links. Links under /go/ send you on to the retailer. Each click records the product, the campaign label in the link if there is one (for example, that it came from Pinterest), and the time. It records no IP address and nothing that identifies you. Cloudflare deletes an uncollected click record after 30 days. Collected records stay in our own click counts.
• ZIP codes typed into the sun-hours calculator. Our server looks up the approximate centre of that ZIP code in a public Census table it carries, sends only those coordinates to NLR for solar data, and caches the answer for a year under the ZIP code alone. The cache does not record who asked.
• Calculator entries. The calculators save what you enter in your own browser (localStorage) so it is still there next visit. We never receive it. Some calculator pages can put your entries into the page address so you can share a plan, and like any page address, that is seen by Cloudflare when the page is requested.
• Ordinary web requests. Like every website, ours is served by a hosting provider that sees your IP address, browser details and the pages you request. For us that is Cloudflare. We also use Cloudflare Web Analytics, which counts page views without cookies and without identifying you.

We do not collect your name, postal address, phone number or payment details. We do not use advertising pixels, the Google or Pinterest tracking tags, or any cookies of our own.

Why we use it

Your email address is used to send what you signed up for: the printable worksheet and price-drop alerts. We use click counts, page-view statistics and request data to keep the site running, secure and worth reading. For visitors in the EU and UK, the legal basis for the mailing list is your consent, which you can withdraw at any time by unsubscribing. For hosting, security and aggregate statistics it is our legitimate interest in running a working, safe site.

Who handles it for us

We use these service providers, and only for the work described:

• Cloudflare hosts the site, runs the signup form and the /go/ links, holds signups until we collect them, blocks abuse, and provides our cookieless page-view statistics.
• MailerLite sends our emails and keeps the mailing list. We may move the list to our own Listmonk server sending through Amazon SES; we will say so here when we do.
• National Laboratory of the Rockies (NLR, formerly NREL) provides the solar data for the sun-hours calculator. Our server sends it the approximate coordinates of the centre of the ZIP code you typed, not the ZIP code and nothing about you.
• BigCommerce serves the product photos, which load straight from the retailer's image host, so that host sees your IP address and browser details like any image request.

We do not sell your personal information, and we do not share it for cross-context behavioral advertising. We would disclose information if the law required it.

Affiliate links and retailer cookies

Watt & Wrench is reader-supported. When you buy through links on our site we may earn an affiliate commission at no extra cost to you. When you follow a /go/ link you leave our site. The retailer, Amazon included, may then set its own cookies and collect data under its own privacy policy, which we do not control. That is how a retailer knows a purchase came from a link here.

Cookies and browser storage

We set no cookies. The only thing our pages store in your browser is the calculator data described above. You can delete it by clearing this site's data in your browser settings.

Do Not Track and Global Privacy Control

We do not track you across other websites, so there is nothing for a Do Not Track or Global Privacy Control signal to turn off. We treat either signal as a request not to sell or share your information, which we do not do anyway.

Your choices and rights

Every email we send has an unsubscribe link. You can also write to hello@wattandwrench.com to ask what we hold about you, to correct it, or to delete it. Depending on where you live (for example California, the EU or the UK), the law may give you these rights. We honor these requests wherever you live, we answer within 30 days, and we will not treat you differently for making one.

Children

This site is not directed to children under 13, and we do not knowingly collect their information. A parent who thinks a child has signed up can write to us and we will delete the address.

Where your data is processed

We are based in the United States and process data there. Our providers may also process it in other countries.

Security

We take reasonable measures to protect the information we hold, and we keep as little as we can. No system is perfectly secure.

Changes to this policy

When we change this policy in a material way, we update the date at the top. Before we change how we use email addresses on our list, we tell the list first.