# A/B test: put "Which size am I?" next to the size selector

> If you put a link to the size guide right next to the size selector instead of at the bottom of the page, then you will get more orders, because doubt about the size stops the purchase exactly when people are choosing.

- Source: https://bixlow.com/en/ideas/size-guide-next-to-selector
- Language: en
- Updated: 2026-11-02
- Publisher: Bixlow

## Why it might work

The moment of greatest doubt on a clothing or footwear page is when "S M L XL" is staring at you. Does this brand run large or small? Am I a medium here? If the guide sits in the footer or in a tab nobody opens, people guess, or they don't choose at all.

A "Which size am I?" link just above or beside the sizes, opening the chart without leaving the page, puts the answer where the question is.


## How to set it up

In Bixlow you describe the change to the agent, it builds it on your site and launches it as an A/B test once you approve it.

1. Make sure your size guide is useful: measurements in centimetres and inches and, if you can, fit advice ("between two sizes? go up").
2. In the variant, add the link right by the selector, opening the guide in a dialog on the same page.
3. Make the dialog close with Escape and return focus to the selector.
4. Run it on product pages with sizes, for all traffic.


## What to measure

|  | Metric |
| --- | --- |
| Primary metric | Orders per visitor |
| Metric that must not get worse | Add-to-carts |
| Where it is measured | Product pages with a size selector |
| After the test | Size-related returns on each version's orders |


> **When I would not test it.** If your products are one size or very standard sizes (socks, say), the doubt does not exist. And if your size guide doesn't really help, the link only leads to a generic chart: fix the guide first.


## FAQ

### Why bring up returns?

Because a good guide can raise orders and also cut size-related returns. Returns arrive weeks later, so check them once the test is over.

### Link or pop-up?

Better if it opens on the product page. If the link goes to another page, the shopper loses what they were looking at.

### What about a size calculator?

That is a more ambitious variant. Start by moving the link, which is cheap; if it works, you have a reason to invest in something bigger.

## Further reading

- [Next idea: star rating below the title](https://bixlow.com/en/ideas/rating-below-title)
- [What an A/B test is](https://bixlow.com/en/glossary/ab-test)
- [Sample size calculator](https://bixlow.com/en/tools/sample-size-calculator)