Privacy policy

Size Chart.io, made by Understory. Last updated 25 October 2026.

Size Chart.io lets a Shopify merchant build size charts and show them on their product pages. This page explains what the app keeps, why, and for how long.

What the app keeps for a merchant

To let you pick products and collections, the app reads product titles, tags, types and vendors from Shopify. It does not keep a copy of your catalog.

What the app keeps about shoppers

Nothing that identifies anyone. When a shopper has allowed analytics in your store's privacy settings, opening a size guide adds one to a daily total for that chart. The app does not store names, emails, IP addresses, cookies or anything else about the shopper. A shopper's cm or inch choice is remembered only in their own browser.

Who else sees this information

No one. We do not sell or share it. It is stored with Cloudflare, which hosts the app.

When you uninstall

The app stops working and its access token is deleted straight away. The chart copy in your store is app data, which Shopify removes with the app. Shopify then asks us to delete the rest of your shop's data within 48 hours, and we do.

Requests about personal data

The app answers Shopify's data requests and deletion requests. Because it keeps no shopper data, there is nothing to send or delete for a shopper.

Contact

Questions or requests: support@understoryapps.com