Cool Image Magnifier vs FastEdge: Shopify Performance Comparison
Both apps score Grade C — FastEdge has the edge with 28 ms vs 46 ms desktop CPU execution.
Both apps provide page speed optimization 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 | Cool Image Magnifier | FastEdge | Faster |
|---|---|---|---|
| Overall Grade | C | C | Tie |
| JS Payload | 172.1 KB | 189.6 KB | Cool Image Magnifier |
| CPU Desktop | 46 ms | 28 ms | FastEdge |
| CPU Mobile | 144 ms | 105 ms | FastEdge |
| Layout Shift | 0.0 | 0.0 | Cool Image Magnifier |
Mobile CPU measured with 4× CDP throttle (mid-range Android). Tested 2026-05-30.
FastEdge — The Faster Option (Grade C)
FastEdge scores Grade C with a JS payload of 189.6 KB and 28 ms desktop CPU execution. Mobile CPU: 105 ms. Even as the faster of the two options, merchants on mobile-heavy stores should weigh its impact on their combined app stack.
View full FastEdge speed report →
Cool Image Magnifier — The Heavier Option (Grade C)
Cool Image Magnifier scores Grade C with a JS payload of 172.1 KB and 46 ms desktop CPU execution. Mobile CPU: 144 ms. This places it in the heavier half of StackConflict’s benchmark dataset — merchants running mobile-first stores should evaluate whether the feature value justifies the performance tradeoff.
View full Cool Image Magnifier speed report →
When to Choose Cool Image Magnifier
- Its unique feature set has no lighter equivalent in StackConflict’s database
- Your store traffic is predominantly desktop
- You have already removed or lightened other heavy scripts to compensate
When to Choose FastEdge
- Its unique feature set has no lighter equivalent in StackConflict’s database
- Your store traffic is predominantly desktop
- You have already removed or lightened other heavy scripts to compensate
Performance Verdict
Result: Comparable — Both apps score Grade C — FastEdge has the edge with 28 ms vs 46 ms desktop CPU execution.
Both apps carry Grade C — see StackConflict’s full Performance rankings for lighter alternatives.
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.