# Star rating summary at top of product page: +15% conversion rate

- Outcome: Won
- Page type: Product page (Ecommerce)
- Elements: Reviews & star ratings
- Test run by: [GrowthRock](https://liftarchive.com/practitioners/growthrock/)
- Commentary by: LiftArchive (our analysis, not theirs)
- Original source: https://growthrock.co/ecommerce-review-ab-test-case-study/
- Page: https://liftarchive.com/test/growthrock-apparel-star-rating-summary-pdp/

Adding a star rating summary near the top of product pages raised conversion rate by 15% and revenue per session by 17% for an apparel brand selling fashion items priced over $100. GrowthRock ran this A/B test and published it on its blog. Add-to-cart rate did not change, so the gain showed up later, at purchase.

## Result

**+15% conversion rate**

- Conversion rate: +15% at 94% significance, just short of the usual 95% bar.
- Revenue per session: +17% at 97% significance.
- Average order value: +2.4%, a small change, so most of the revenue gain came from more orders.
- Add-to-cart rate: no change between the two versions.

## Control

Product pages had customer reviews at the bottom, but no star rating summary near the product name.

## Variant

A star rating summary was added near the top of each product page, with the full reviews still lower down.

## Why it likely won (our reading)

- Shoppers often add pricier fashion items to cart as a bookmark, then come back to the product page to decide. The stars may have helped at that second visit.
- A rating near the top gives social proof without making shoppers scroll to the reviews.
- For $100+ items that are mulled over, signs that other buyers were happy can ease doubts about fit and value.

## Caveats

The conversion rate lift reached 94% significance, below the 95% convention. Sample size, duration and test date were not shared.

## How to run this test

- Hypothesis: If we show a star rating summary near the top of product pages, then more visitors will buy because positive social proof is visible when they weigh the purchase.
- Primary metric: Conversion rate
- Guardrail: Revenue per session
- Guardrail: Average order value
- Guardrail: Add-to-cart rate
- Who should test it: Stores that already collect reviews but only show them low on the page, especially for considered purchases. It may not help if your ratings are few or mixed, or if a luxury brand image depends on keeping reviews off the page.

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Credit: GrowthRock ran this test and owns the result. Summary and commentary by LiftArchive (https://liftarchive.com/test/growthrock-apparel-star-rating-summary-pdp/).
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.