SEO, Performance & Data

Shopify Core Web Vitals Optimisation

For AU Shopify and Plus operators whose storefront passes on the desk but fails in the field. We fix LCP, CLS and INP against real-user data, so pages feel instant and search sees a faster site.

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90+

Avg Lighthouse at launch

+28%

Avg conversion lift

CrUX

Real-user field data, not lab-only

20+

Shopify builds shipped

28-day

Field window we target for pass

When lab scores lie and real users bounce

Lighthouse says 95. Search Console flags the same URLs as "needs improvement". That gap is the field data, what your actual visitors experience on mid-range phones and real networks, and it's what Google ranks on.

Passing in the lab, failing in the field

A synthetic test on fast hardware hides the jank real shoppers hit. CrUX is the source of truth, and it disagrees.

Hero images that arrive late

Poor LCP on product and collection pages, unpreloaded heroes, oversized assets, render-blocking theme code, makes the store feel slow above the fold.

Layout that jumps as it loads

CLS from banners, web fonts, lazy images without dimensions and injected app content shifts the page under a shopper's thumb.

Sluggish taps on mobile

INP problems from heavy third-party scripts and long main-thread tasks mean variant selectors, filters and add-to-cart feel laggy.

Apps quietly taxing every page

Review widgets, upsell apps and pixels stack up. Each adds JavaScript that blocks the main thread and drags interaction latency.

No way to prove the win

Without field monitoring you can't tell leadership whether the last change helped or hurt, or defend the score when it slips.

Scope at a glance

What we own, what stays with you, and what sits outside this engagement.

Included	Your side	Out of scope
Metrics	LCP, CLS and INP across key templates	Access to Shopify admin and analytics	Server-side rendering / headless rebuild
Assets	Image sizing, formats, preload, fonts	Sign-off on any visual trade-offs	New photography or art direction
Scripts	Theme JS and app-script audit and tuning	Decisions on apps we recommend removing	Building custom replacement apps
Proof	Before/after field + lab reporting	Confirming business metrics to track	Ongoing paid-media or SEO campaigns

Is this the right engagement

A strong fit if

You're on Shopify or Shopify Plus and Search Console flags Core Web Vitals as needs improvement or poor
Real-user (field) scores lag your Lighthouse numbers and you need the gap closed
You've added apps and pixels over time and page weight has crept up
You want measurable LCP, CLS and INP gains tied to conversion and search
You need the fix documented so your team can keep the score green

Not the right fit if

You're not on Shopify, we're Shopify-only, by design
You want a headless Hydrogen rebuild (that's a separate build engagement we can scope)
You expect a one-click app to fix it with no theme changes
Your priority is net-new features, not performance and stability
You need guaranteed rankings, we improve signals and UX, not promises

What Core Web Vitals work covers

A focused pass across the three metrics Google measures, grounded in your real-user data and verified page by page.

What's included

Field-data audit from CrUX and Search Console, not lab-only scores
LCP fixes: hero preloading, image sizing, render-blocking cleanup
CLS fixes: reserved space, font-loading strategy, stable app slots
INP fixes: script deferral, main-thread work reduction, event handler tuning
Prioritised backlog ranked by impact on metric and revenue

Technical deliverables

Responsive, correctly-sized images with modern formats and lazy loading
Preload and preconnect for critical assets and fonts
Theme Liquid and JavaScript refactor to cut render-blocking work
Third-party and app script audit with defer, remove or replace calls
Before-and-after field and lab report you can share internally

Monitoring & handover

Field monitoring so regressions surface before Search Console does
Documented change log and a maintenance checklist for your team
App-install guidance so future apps don't undo the gains
Optional retest and tune-up after the 28-day field window updates

How we run it

A tight, measurable sequence, typically 3 to 6 weeks, then a field-data recheck once real-user data catches up.

Field-data audit

Pull CrUX and Search Console data, run lab traces on real templates, and pinpoint which URLs and metrics are actually failing. Week 1.

Diagnose & prioritise

Trace each failure to its cause, hero, font, script or app, and rank fixes by metric impact and revenue. Week 1.

LCP & CLS fixes

Preload critical assets, size and modernise images, reserve layout space and stabilise fonts on key templates. Weeks 2–3.

INP & script diet

Defer non-critical JavaScript, cut main-thread work and audit app scripts so taps respond fast. Weeks 3–4.

Verify in staging

Retest lab scores, confirm no visual or functional regressions, and check every template on real mobile hardware. Week 4–5.

Ship & monitor

Deploy, set up field monitoring and hand over the change log and maintenance checklist. Week 5.

Field recheck

Revisit once the 28-day field window updates, confirm the pass and tune anything still lagging.

How we protect the result

Performance work is only worth it if nothing else breaks and the score stays green.

Real-user field data (CrUX) treated as the source of truth, not lab-only scores
Every template checked on mid-range mobile hardware, not just desktop
No visual or functional regressions signed off before deploy
WCAG 2.1 AA maintained through every performance change
Field monitoring in place so regressions surface early
Change log documented so your team can maintain the gains

Investment

Pricing is scoped after a short discovery, it depends on how many templates fail, how heavy your app stack is, and how far the field data sits from a pass. Typical AUD bands below.

Number of failing templates and URLs (product, collection, home, cart)How many metrics fail, one, two or all three of LCP, CLS, INPSize and complexity of your app and third-party script stackTheme age and how much Liquid and JavaScript needs refactoringWhether ongoing field monitoring and a follow-up tune-up are included

Targeted fix

$3,500–$6,500

One or two failing metrics on a clean theme with a light app stack.

Full CWV pass

$7,000–$14,000

All three metrics across key templates, heavier app stack, before/after reporting.

Performance retainer

from $1,500/mo

Ongoing monitoring, regression fixes and periodic tune-ups. Scoped to your store.

Core Web Vitals FAQs

Lighthouse is a lab test on simulated hardware. Core Web Vitals in Search Console use field data, CrUX, from your real visitors. Google ranks on the field data, so we optimise against that, not just the lab score.

The fixes ship in roughly 3 to 6 weeks. But field data updates over a rolling 28-day window, so Search Console typically reflects the pass a few weeks after deploy. We recheck once that window catches up.

Core Web Vitals are a confirmed ranking signal, though one of many. We improve the signal and the shopper experience, faster pages usually help conversion as much as search. We don't promise specific rankings.

Yes. We audit app scripts and change how and when they load, deferring, reordering or, where an app is clearly hurting performance, recommending a lighter alternative. We don't remove anything without your sign-off, and functionality is verified before deploy.

Interaction to Next Paint measures how quickly the page responds to taps and clicks. It replaced First Input Delay as a Core Web Vital, and it's often the hardest to pass because heavy app and theme JavaScript blocks the main thread on mobile.

You do. It's your theme, your code, and we hand over a documented change log plus a maintenance checklist. There's no lock-in and no proprietary layer you have to keep us on for.

In most cases, yes. Core Web Vitals work is targeted, image handling, preloading, font strategy and script tuning within your existing theme. If the theme is fundamentally holding you back, we'll say so and scope a rebuild separately.

We set up field monitoring so regressions surface before Search Console flags them, and give your team guidance on installing future apps without undoing the gains. An optional retainer covers ongoing monitoring and tune-ups.

Yes to Plus. For headless Hydrogen storefronts, performance is baked into the build, we can scope that as a separate engagement rather than a retro-fit.

Related services

Turn a failing field score into a green pass

Send us your store and Search Console access. We'll pinpoint which URLs and metrics are failing in the field and scope the fix, no obligation.

Book a call

Store URL Which CWV metric is flagged Shopify or Shopify Plus