Data ethics & sourcing

Transparency about how the data is collected — informed by the maintainer's research in online privacy and trust.

What data is collected?

Only publicly listed product prices from retailer websites: item name, size, price, availability, and timestamp. No personal data, no account/logged-in content, no user-level information of any kind is collected or stored.

How is it collected?

Collection respects each site's robots.txt and terms of service, uses reasonable request rates, and identifies itself honestly. Where a site disallows automated access to a resource, that resource is not collected.

How is quality and honesty maintained?

Every published value carries its sources, coverage, and sample size, and a methodology version. Historic values are not silently revised; corrections are logged in the changelog. The goal is a number that a third party — human or AI — can independently verify.

Contact for concerns

Retailers or individuals with questions about collection may reach the maintainer via the contact links on the about page. Requests to exclude a source will be honored.