Sizer privacy policy

Effective 3 October 2026

Sizer is a Chrome extension that shows which clothing size to buy on product pages. It is built to work without collecting anything about you.

What Sizer stores

Your fit profile: the measurements you enter, the clothes you add and how they fit, your preferred units and your fit preference. It is saved with Chrome’s own storage in your Chrome profile. If Chrome sync is on, Chrome keeps it in step across your devices, the same way it does for your other extension settings.

What Sizer reads

On supported shops, and on any page where you click the Sizer icon and ask it to, Sizer reads the product page in your browser: the brand, the product details, the sizes and whether they’re in stock. This happens on your device and nothing from the page is saved or sent anywhere.

What Sizer sends

Nothing about you. Once a day Sizer downloads the latest brand size charts from its own database (a Supabase project). That request carries no data from you or from the pages you visit: no profile, no page, no identifier, only the request for the chart list, which is the same for everyone.

One thing does go the other way. When a product page has customer reviews, Sizer counts how many say the item runs small, runs large or fits true to size, and sends that tally to the same database, so that shoppers looking at the same style on another shop can use it. The tally carries the brand, the style name, the shop’s hostname and the counts. It does not carry your profile, the page address, the review text, or anything that identifies you. A random id generated at install, unrelated to you or your browser, lets a later read of the same page replace the earlier tally instead of adding to it. When Sizer sizes a product it also asks the database for the pooled tally of that style; that request carries only the brand and style name.

Sizer has no accounts, no analytics and no advertising. It doesn’t sell, share or transfer any data, and it doesn’t use data for anything other than showing you your size.

Deleting your data

Remove the clothes and measurements on Sizer’s fit profile page, or uninstall the extension, which deletes everything it stored.

Changes

If this policy changes, the new version will be posted here with a new effective date.