VWO vs Zepto Product Personalizer: Shopify Performance Comparison
Both apps score Grade B — VWO has the edge with 13 ms vs 24 ms desktop CPU execution.
Both apps provide personalization and product recommendations functionality for Shopify stores. This page presents StackConflict’s independent lab results for both — measured in a clean-room environment with no other apps installed.
Head-to-Head Metrics
| Metric | VWO | Zepto Product Personalizer | Faster |
|---|---|---|---|
| Overall Grade | B | B | Tie |
| JS Payload | 89.86 KB | 92.97 KB | VWO |
| CPU Desktop | 13 ms | 24 ms | VWO |
| CPU Mobile | 48 ms | 67 ms | VWO |
| Layout Shift | 0.0 | 0.0 | VWO |
Mobile CPU measured with 4× CDP throttle (mid-range Android). Tested 2026-05-30.
VWO — The Faster Option (Grade B)
VWO scores Grade B with a JS payload of 89.86 KB and 13 ms desktop CPU execution. Mobile CPU: 48 ms. It passes every StackConflict threshold for payload, CPU, and layout stability — making it safe to install on any storefront including mobile-first stores where Time-to-Interactive directly impacts conversion.
Zepto Product Personalizer — The Heavier Option (Grade B)
Zepto Product Personalizer scores Grade B with a JS payload of 92.97 KB and 24 ms desktop CPU execution. Mobile CPU: 67 ms. Performance is acceptable but worth monitoring, particularly on stores with high mobile traffic share.
View full Zepto Product Personalizer speed report →
When to Choose VWO
- You need its specific features and can monitor its mobile impact
- Your other apps are lightweight (Grade A) so there is headroom
- You are on desktop-skewed traffic where CPU cost matters less
When to Choose Zepto Product Personalizer
- You need its specific features and can monitor its mobile impact
- Your other apps are lightweight (Grade A) so there is headroom
- You are on desktop-skewed traffic where CPU cost matters less
Performance Verdict
Result: Comparable — Both apps score Grade B — VWO has the edge with 13 ms vs 24 ms desktop CPU execution.
About This Test
StackConflict measures each Shopify app in an isolated clean-room environment — a single development store, no other scripts, Playwright-controlled browser. V8 CPU cost is the ScriptDuration delta before and after injection. CLS is captured from the same browser session. Results represent the median of three independent runs with outliers removed.
Data from the StackConflict Lab. Last updated 2026-05-30.