# Size guide pop-up on mobile product pages: +2.66% conversion rate

- Outcome: Won
- Page type: Product page (Ecommerce)
- Elements: Variant, size & option selectors, Popups & email capture
- Test run by: [ConvertPolo](https://liftarchive.com/practitioners/convertpolo/)
- Commentary by: LiftArchive (our analysis, not theirs)
- Original source: https://wingify.com/success-stories/theater-convertpolo-revenue/
- Page: https://liftarchive.com/test/theater-pdp-size-guide-popup/

A prominent 'Size Guide' link that opens a pop-up on Theater's mobile product pages raised conversion rate by 2.66% and revenue per visitor by 2.14%. ConvertPolo ran this A/B test for Theater, a fashion and lifestyle brand, and it was published as a VWO case study. The lift is small and no significance level was given.

## Result

**+2.66% conversion rate**

- Conversion rate: +2.66% against the page without a size guide.
- Revenue per visitor: +2.14%.
- Both lifts are small. Without a significance level, they may be within normal noise.

## Control

The mobile product page had no easy-to-find sizing help.

## Variant

A visible 'Size Guide' trigger opened an instant pop-up overlay, so shoppers could check sizing without leaving the page.

## Why it likely won (our reading)

- Fit doubt is a common reason to delay buying clothing online. A size guide answers it in place.
- A pop-up keeps shoppers on the product page instead of sending them elsewhere to find sizing.
- The small lift may mean only some shoppers were unsure of their size, or only some products were fit-sensitive.

## Caveats

The lift is small and no sample size, test duration or significance level was published, so treat it as a weak signal.

## How to run this test

- Hypothesis: If we add a prominent size guide link that opens a pop-up near the size picker, then more shoppers will buy, because they can confirm fit without leaving the page.
- Primary metric: Conversion rate from product page sessions
- Guardrail: Revenue per visitor
- Guardrail: Size-related return rate
- Guardrail: Size guide open rate
- Who should test it: Apparel and footwear stores where fit varies between products. Expect a small lift, so you'll need plenty of traffic to detect it; low-traffic stores may never reach a clear result.

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Credit: ConvertPolo ran this test and owns the result. Summary and commentary by LiftArchive (https://liftarchive.com/test/theater-pdp-size-guide-popup/).
Usage: Free to use, quote and build on, with credit and a link: name the practitioner or organization that ran the test and link to its LiftArchive page. The results belong to the practitioners who ran and shared them; the summaries and commentary are LiftArchive's.