← All apps Email Marketing Mailchimp vs Omnisend
🔬 Lab Findings 🔧 Stack Builder
⏳ Pending
?
Mailchimp
Data pending
★ 4.8 · 1,239 reviews
Under Review
VS
⚡ Faster
B
Omnisend
82.9 KB · 39 ms CPU
★ 4.8 · 2,952 reviews
Acceptable
Metric Mailchimp Omnisend
Overall Grade A B
JS Payload 0.11 KB 82.9 KB
CPU Desktop Pending ⏳ 39 ms
CPU Mobile Pending ⏳ 92 ms
Layout Shift 0.0006 0
Merchant Rating ★ 4.8 (1,239) ★ 4.8 (2,952)

Mailchimp vs Omnisend: Shopify Performance Comparison

Data pending for Mailchimp — 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 Mailchimp and Omnisend provide email marketing and automation functionality for Shopify stores.

What We Know: Omnisend (Benchmarked)

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

MetricOmnisend
Overall GradeB
JS Payload82.9 KB
CPU Desktop39 ms
CPU Mobile92 ms (0.1s)
Layout Shift0.0

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

View full Omnisend speed report →

Pending: Mailchimp

StackConflict’s scanner detected that Mailchimp 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 Mailchimp will appear here automatically.

View Mailchimp 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.


Omnisend data from the StackConflict Lab (2026-05-30). Mailchimp data pending.