Landing Page Speed
Landing page speed is the time from click to a usable, interactive page — and every 100ms costs conversions. Here's what "fast enough" looks like and what typically slows a store down.
Landing Page Speed
How quickly a landing page becomes visible and interactive after a click — typically measured by Largest Contentful Paint (LCP), with 2.5s the threshold for 'good'.
Landing page speed is the elapsed time between a visitor clicking an ad, link, or organic result and your page being usable — visually rendered, scrollable, and ready to accept input. The dominant industry metric is Largest Contentful Paint (LCP), Google's Core Web Vital that times when the biggest above-the-fold element (usually the hero image or H1) finishes painting. Under 2.5 seconds is 'good', 2.5-4s is 'needs improvement', and over 4s is 'poor'.
Speed matters on two fronts: it directly shapes conversion rate (slow pages lose buyers before they ever see the offer) and it feeds Google Ads Quality Score and organic rankings, lowering CPCs for fast pages and raising them for slow ones.
The 2.5-second target isn't arbitrary. Google's own field data across millions of sessions shows that bounce probability rises 32% when LCP moves from 1s to 3s, and more than doubles by 6s. Mobile sessions on 4G are where most stores miss the target — desktop usually passes, mobile usually doesn't.
Three culprits cause the vast majority of slow landing pages. Oversized hero images (uncompressed JPEGs or PNGs served at 3000px wide) are the single biggest offender. Third-party scripts — chat widgets, heatmap tools, review widgets, multiple analytics tags — block the main thread. And custom web fonts loaded synchronously delay text rendering by 400-800ms. Landing page optimization work that ignores speed leaves money on the table no matter how good the copy is.
Conversion Impact ≈ Current CR × (1 - 0.07)^((Current LCP - Target LCP) / 1s)
Current CR
Current conversion rate
Your existing landing page conversion rate as a decimal (e.g. 0.024 for 2.4%).
Current LCP
Current LCP in seconds
Your measured Largest Contentful Paint on mobile, p75.
Target LCP
Target LCP in seconds
Where you want to land — typically 2.5s or better.
0.07
Per-second decay
Industry rule of thumb: conversion drops ~7% per extra second of LCP above target.
A Shopify apparel store with a 2.4% conversion rate and 4.8s mobile LCP wants to model the upside of getting to 2.5s.
Current CR: 2.4%
Current LCP: 4.8s
Target LCP: 2.5s
→ Projected CR ≈ 2.4% × (0.93)^2.3 ≈ 2.04% — meaning the slow page is costing roughly 17% of conversions, or ~€18k/month on €105k landing-page revenue.
Even rough modelling shows speed work has measurable revenue upside; this is why speed audits sit alongside copy and offer testing in a serious CRO program.
Benchmarks vary widely by platform and theme. A vanilla Shopify Dawn theme on a fast host loads in roughly 1.8s on mobile; the same store after adding six apps with embedded scripts can climb past 5s. WooCommerce on shared hosting sits at the slow end; Magento on dedicated infrastructure trends faster than most expect.
Median mobile LCP by platform and configuration (p75 field data)
| Platform / setup | Median LCP (mobile) | % passing Core Web Vitals | Typical bottleneck |
|---|---|---|---|
| Shopify, default theme, ≤3 apps | 1.8s | 78% | Hero image |
| Shopify, heavy theme, 6+ apps | 4.2s | 31% | Third-party scripts |
| WooCommerce, shared hosting | 3.9s | 34% | Server response (TTFB) |
| WooCommerce, managed hosting | 2.6s | 58% | Plugin bloat |
| Magento 2, dedicated host | 2.3s | 64% | JS bundle size |
| Headless (Next.js + Shopify) | 1.5s | 85% | Font loading |
Read the table as a diagnostic: if your store is on Shopify with 4s+ LCP, the fix is almost certainly app/script audit and hero image compression, not hosting. If you're on WooCommerce with shared hosting, the fix starts at the server. Treating every slow page the same way is why generic 'speed optimization' projects underdeliver.
Landing page speed FAQ
Under 2.5 seconds Largest Contentful Paint on mobile (p75), which is Google's 'good' threshold. Pages above 4s are classified 'poor' and will lose both conversions and Quality Score.
Yes. Page experience feeds Quality Score, which directly multiplies your effective CPC. A landing page that moves from 'poor' to 'good' Core Web Vitals typically sees 10-25% lower CPCs on the same keywords, holding bid strategy constant.
Speed is a foundational layer of landing page optimization — no amount of copy, design, or offer testing compensates for visitors bouncing before the page renders. Most CRO programs audit speed first because it's a multiplier on every other improvement.
Oversized, uncompressed hero images. A 2MB JPEG served at full resolution on mobile can add 1.5-3s to LCP by itself. Compressing to WebP and serving responsive sizes typically cuts this by 70-90%.
Yes, dramatically. Each embedded script — chat, reviews, upsell, heatmap, additional analytics — adds main-thread blocking time. A Shopify store with 8+ apps typically loads 2-3x slower than the same store with 2-3 apps.
No. The hero image is your LCP element by definition; lazy-loading it makes LCP worse. Lazy-load everything below the fold instead, and preload the hero with `<link rel='preload'>` plus a `fetchpriority='high'` attribute.
Use field data, not lab data. PageSpeed Insights shows real Chrome user data (CrUX) for your URL — that's what Google ranks on. Lab tools like Lighthouse are useful for debugging but don't reflect what real users on real devices experience.
Both matter, but HTTPS overhead is negligible on modern servers. A CDN matters most if your audience is geographically spread; for a store selling only in one country with a regional host, CDN gains are smaller than image and script optimization.
Sometimes, but usually not on its own. Most slowdown comes from installed apps and merchant-uploaded assets, not the theme itself. Switching to a lighter theme without auditing apps typically yields 10-20% improvement, not the 50%+ many merchants expect.
Well-built Shopify stores hit 1.2-1.8s LCP on mobile. Headless setups (Next.js, Hydrogen) reach sub-1s. Below 1s requires aggressive image optimization, edge rendering, and minimal third-party scripts — diminishing returns kick in past 1.5s for most stores.
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