← All apps Social Proof Foursixty vs ProveSource
🔬 Lab Findings 🔧 Stack Builder
⚡ Faster
B
Foursixty
107.52 KB · 17 ms CPU
★ 4.9 · 133 reviews
Acceptable
VS
⏳ Pending
?
ProveSource
Data pending
★ 5 · 82 reviews
Under Review
Metric Foursixty ProveSource
Overall Grade B C
JS Payload 107.52 KB 354.72 KB
CPU Desktop 17 ms Pending ⏳
CPU Mobile 39 ms Pending ⏳
Layout Shift 0.0006 0
Merchant Rating ★ 4.9 (133) ★ 5 (82)
⚡ Lab-Verified Fix Keep ProveSource and reduce its speed impact with a dedicated script optimizer: View Booster Page Speed Lab Report →

Foursixty vs ProveSource: Shopify Performance Comparison

Data pending for ProveSource — our scanner captured only the async loader stub for this app. Full bundle metrics are being collected from live Shopify storefronts. Once available, this page will show a complete head-to-head comparison.

Both Foursixty and ProveSource provide social proof and FOMO notifications functionality for Shopify stores.

What We Know: Foursixty (Benchmarked)

Foursixty has been measured in StackConflict’s clean-room lab:

MetricFoursixty
Overall GradeB
JS Payload107.52 KB
CPU Desktop17 ms
CPU Mobile39 ms (0.0s)
Layout Shift0.0006

Grade B means Foursixty passes every StackConflict threshold — safe to install on any storefront including mobile-first stores.

View full Foursixty speed report →

Pending: ProveSource

StackConflict’s scanner detected that ProveSource uses an async JavaScript loader — a small stub that only initialises its full bundle on a real, authenticated Shopify storefront. This means our lab environment captured the tiny stub file only, not the production bundle that actually runs on live stores.

We are collecting real bundle data by scanning public Shopify storefronts. Once captured, the head-to-head metrics for ProveSource will appear here automatically.

View ProveSource on Shopify App Store →

About This Test

StackConflict measures each Shopify app in an isolated clean-room environment — a Playwright-controlled browser with no other scripts installed. V8 CPU cost is the ScriptDuration delta measured before and after bundle injection. Mobile CPU applies the standard 4× Lighthouse slowdown factor.


Foursixty data from the StackConflict Lab (2026-05-30). ProveSource data pending.