← All apps Email Marketing Flodesk vs Sendlane
🔬 Lab Findings 🔧 Stack Builder
⚡ Faster
C
Flodesk
163.88 KB · 29 ms CPU
Heavy
VS
⏳ Pending
?
Sendlane
Data pending
★ 4.3 · 15 reviews
Under Review
Metric Flodesk Sendlane
Overall Grade C B
JS Payload 163.88 KB 62.64 KB
CPU Desktop 29 ms Pending ⏳
CPU Mobile 66 ms Pending ⏳
Layout Shift 0 0
Merchant Rating ★ 4.3 (15)

Flodesk vs Sendlane: Shopify Performance Comparison

Data pending for Sendlane — 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 Flodesk and Sendlane provide email marketing and automation functionality for Shopify stores.

What We Know: Flodesk (Benchmarked)

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

MetricFlodesk
Overall GradeC
JS Payload163.88 KB
CPU Desktop29 ms
CPU Mobile66 ms (0.1s)
Layout Shift0.0

Grade C indicates Flodesk carries a significant JavaScript footprint. Check the full report for lighter alternatives in this category.

View full Flodesk speed report →

Pending: Sendlane

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

View Sendlane 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.


Flodesk data from the StackConflict Lab (2026-05-30). Sendlane data pending.