Where is the size guide, and why does it show on products without sizes?

Where the Volume size guide lives, how it is matched to an option, and why it appears on products with no variants.

The size guide is not a section. It lives inside the Variant picker block of the Product overview section, under the Size guide header — which is why it is easy to miss.

1

Open the block

In Customize, open a product template, expand the Product overview section and click the Variant picker block. Scroll to the Size guide header.

2

Name the option it attaches to

Size label holds the option name the guide should sit next to — Size by default. The match is exact and case-insensitive, so an option called Sizes or UK size will not be found. List several names separated by commas if your catalogue is inconsistent, for example Size, Legs size.

If a product has more than one matching option, the link is rendered once, next to the first match.

3

Give it content

Fill in Content from rich text, Content from page, or both — the rich text is rendered first, the page content below it. Content from page takes a normal Shopify page created under Online Store → Pages.

Nothing appears until at least one of these two is filled in, even if Size label matches.

Why it shows on products with no sizes

This is the one case where the Size label match is skipped. On a product with no variants at all (a single default variant), Volume renders the size guide link whenever Content from rich text or Content from page is filled in — there is no option to match against, so the theme shows it unconditionally.

Products that do have variants behave as expected: if none of their options matches Size label, no link appears.

The fix is to stop hard-coding the content in the block and feed it per product instead. Create a metafield, fill it in only on the products that need a chart, and connect it to Content from rich text or Content from page as a dynamic source. Products without the metafield then have nothing to show, so nothing is rendered — variants or not. Full walkthrough in Size Guide.

The pop-up renders the page's content, not the page's own theme template. Sections you added to the size chart page in the theme editor will not appear inside the pop-up — put the chart in the page's rich-text body.

Two more fields in the same group are worth knowing: Show ruler toggles the little ruler icon on the link, and Style switches the pop-up between Popover and Drawer.

The link text itself is the translation string Size Guide, editable under Online Store → Themes → … → Edit default theme content.