Custom Size Guide on Shopify Dawn

Topic summary

A user is seeking help to build a custom size guide for Shopify product pages using the Dawn theme.

Key Requirements:

  • Interactive size selector allowing customers to toggle between UK, US, and EU sizing systems
  • When a sizing system is selected (via tabs), the entire size table updates to display all sizes in that system
  • Must be implemented with custom code (HTML/CSS/JavaScript) without third-party apps
  • Should be positioned in the top-right corner, above the size selection options
  • Needs responsive design for both mobile and desktop

Visual Reference:
Three screenshots were provided showing the desired tabbed interface and table layout.

Status:
The discussion remains unanswered. The original poster followed up asking if anyone has a solution, but no responses or code implementations have been provided yet.

Summarized with AI on October 30. AI used: claude-sonnet-4-5-20250929.

Hi there,

I’m looking to create a custom size guide on my Shopify product pages and need some assistance. Here’s what I’m aiming for:

UK, US, EU Size Selector:
I want to set up a size guide where customers can choose a UK size and automatically see the corresponding US and EU sizes in a simple table format.

When a customer selects a UK size, the UK size options will be shown by default. If they want to view the corresponding sizes in US or EU, they can simply click on the US or EU tab. Once clicked, all the sizes will switch to the selected sizing system.

No App Needed:
I’d like to implement this using custom code (HTML, CSS, or JavaScript), without relying on any third-party apps.

Clean, User-Friendly Design:
The size guide should fit seamlessly into the product page and look great on both mobile and desktop. Ideally, it would be positioned just above the actual size options, on the top-right corner.

The size selector should look like this:

Anyone have a solution for this?