What is the product_data_storage cookie?
product_data_storage is a localStorage key used by the Magento (Adobe Commerce) e-commerce platform, rather than a traditional HTTP cookie. It is created by the theme's or module's JavaScript that powers features such as the product comparison list, recently viewed products, or other catalog-related interface elements.
It typically appears when a visitor browses an online store built on Magento and interacts with product pages, category listings, or comparison/recently-viewed widgets, at which point the front end saves this data locally for quick display on return visits.
What data it stores
It generally stores product identifiers and related metadata (for example IDs, names, images, prices) as a serialized JavaScript object (JSON), needed to quickly rebuild the lists shown on the site (compared or recently viewed products). The exact value format varies depending on the theme and modules installed on a given store.
Being localStorage, the data stays stored locally in the visitor's browser and is not automatically sent to the server with every request, unlike HTTP cookies; it is read only by that site's Magento scripts via JavaScript.
What it is used for
Its main purpose is functional: it lets the site retain, across pages or sessions, the list of products a user has compared or recently viewed, without an extra server request. This keeps the store's interface fast and consistent for the visitor.
For the store administrator, this storage supports standard Magento features (product comparison, "recently viewed") and is not intended for advertising tracking or cross-site analytics.
Does it require consent?
In CookieFix's classification, product_data_storage falls under the preferences (functional) category. Although it is localStorage rather than a cookie, the ePrivacy Directive (transposed in Romania via Law 506/2004) and ANSPDCP guidance treat browser data storage similarly to cookies, regardless of the underlying technology.
- If the storage serves strictly essential cart or catalog functionality, it may be treated as necessary and simply disclosed in the cookie policy.
- If it is also used for broader personalization or combined with other non-essential purposes, it is advisable to condition it on visitor consent under the preferences category.
- The site operator should list it explicitly in the cookie policy, with its actual purpose and duration, verified through periodic scanning of the store.
How to block or delete product_data_storage
Visitors can delete this entry from browser settings, under the site data storage section (Site Data/Local Storage), or by using private browsing mode; removing it does not break the store's core functions, it only resets locally saved lists.
For site administrators, a CMP such as cookiefix.ro can automatically block the Magento scripts that write to localStorage until the visitor gives consent for the preferences category, helping ensure conditional script loading.
Frequently asked questions
It's a localStorage entry, not an HTTP cookie, but it is treated similarly under ePrivacy rules because it stores data in the visitor's browser.
It is set by the Magento (Adobe Commerce) platform's JavaScript, used by online stores built on this technology.
It depends on usage: if it only supports essential catalog functions it may be treated as necessary, but if it drives broader personalization, consent under the preferences category is recommended.
Through browser settings, in the site data section (Local Storage/Site Data) for that domain, or by browsing in private mode.