Card Stack Optimizer

Privacy policy

Last updated: October 2, 2026

This page explains what information Card Stack Optimizer collects and how it is used. We collect as little as we can.

Information we collect

Email address. If you sign up for the free calculator or our emails, we collect your email address through our email service provider, Systeme.io, so we can send what you asked for and occasional updates. We never ask for card numbers, account numbers, or credit reports. You can unsubscribe at any time using the link in any email.

Contact messages. If you email us, we receive your email address and whatever you write.

Site analytics. We use a privacy-focused analytics service, Cloudflare Web Analytics, to see aggregate traffic such as which pages are visited. It does not use cookies or track individuals across sites.

Embedded video

Some pages include YouTube videos. We load them in a privacy-enhanced mode and only after you click to play. Once a video loads, YouTube may collect information under its own privacy policy.

If you click an affiliate link, the company you are sent to may use cookies to record that you arrived from this site, so we can be credited for a referral. We do not control those cookies. Review that company's privacy policy for details.

The calculator

The calculator opens as a Google Sheet that you copy to your own account. Numbers you enter into your copy are kept in your copy. We do not receive them.

How we use information

We use your email to deliver the materials you requested and to send updates about new guides, card changes, and resources. We do not sell your personal information.

Sharing

We share information only with service providers that help us operate the site and send email, and where required by law. Those providers may process information on our behalf under their own terms.

Your choices

You can unsubscribe from emails at any time. You can ask us to delete your email address or to tell you what we hold about you by writing to us at info@cardstackoptimizer.com.

Children

This site is intended for adults. We do not knowingly collect information from children.

Changes

We may update this policy. The date at the top of the page shows when it was last changed.

Contact

Questions about this policy: info@cardstackoptimizer.com.

Next steps

  • 01Disclaimer and affiliate disclosure

    Card Stack Optimizer is educational content, not financial, legal, or tax advice. Read about accuracy, sample households, third parties, and affiliate links.

  • 02Contact

    Contact Card Stack Optimizer with questions, corrections, or reports of outdated card terms. Email only; we cannot give personal advice.

  • 03About Card Stack Optimizer

    Card Stack Optimizer is a free educational resource that shows what credit cards return in dollars, with every rate traced to the issuer's own page.