Add a Free Shoe Size Converter to Your Website

Drop a self-contained shoe size converter onto any site in one line. It converts US, EU, UK and CM men's sizes, shows brand fit verdicts (Nike, Adidas, New Balance, ASICS, Brooks), and works without API keys or runtime calls to ShoeSizeguide after the script loads. The widget script does not track users; the partner request form on this page is separate.

Live preview

This is the real widget, running right here. Pick a size to see it convert.

Copy the code

Best option: the widget renders inline and inherits your page width. 

<script src="https://shoesizeguide.com/widget/size-guide-widget.js"></script>
<size-guide-widget brand="nike" locale="en" theme="light"></size-guide-widget>

Attributes: brand (nike, adidas, new-balance, asics, brooks), locale (en, en-gb), theme (light, dark). All are optional — leave brand off for a plain converter.

Implementation notes for partners

  • Compatibility channel: Use /widget/size-guide-widget.js as the current v1-compatible script. Supported attributes (brand, locale, theme) will not be removed without a new URL.
  • Strict CSP: For the Web Component, allow script-src https://shoesizeguide.com. For the iframe fallback, allow frame-src https://shoesizeguide.com.
  • Fallback embed: If a CMS blocks custom scripts, use the iframe snippet. It isolates CSS, keeps the converter lazy-loaded, and avoids host-page JavaScript conflicts.
  • License and attribution: The public widget and JSON data are CC BY 4.0 with attribution to ShoeSizeguide.com. Do not remove the Powered by link unless a custom agreement says so.
  • JSON refresh: Cache JSON API responses for up to 24 hours and refresh from _meta.last_modified, Last-Modified, or ETag rather than polling every page view.

Brand JSON endpoint

If you need source-backed size data without rendering the widget, use the static JSON endpoint. It is generated from the same Content Collections as the brand pages and widget. 

GET https://shoesizeguide.com/api/sizes/nike.json
  • Fields: gender, foot_length_mm, fit_offset, confidence, width_availability, sizes, and provenance.
  • Headers: public 24-hour cache, CORS *, Last-Modified, and weak ETag.
  • License: CC BY 4.0 with attribution to ShoeSizeguide.com.

Add it in 3 steps

  1. Copy the Web Component or iframe snippet above.
  2. Paste it into your page's HTML where you want the converter to appear.
  3. Customize the brand, locale and theme attributes — that's it, no build step.

Questions

Can I remove the attribution?

No — attribution is required and helps your users trust the data. The "Powered by ShoeSizeguide.com" link stays so visitors know where the conversions come from and can check the full, sourced size guide.

Does it slow down my site?

No. The Web Component is a single small script with no external dependencies and makes no runtime data requests after it loads — all conversion data is built in. It renders instantly and won't shift your layout.

Can I present this as my brand's official size guide?

No. The widget shows independent, sourced conversions and must not be positioned as a shoe brand's official chart. It's a neutral converter you can offer alongside your own content.

Need a white-label or branded version?

For custom styling, additional brands, or a partnership without the standard attribution, use the form below or email partners@shoesizeguide.com.

We use your email only to reply about widget/API partnership options. We do not add you to a newsletter from this form. See the privacy policy.