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Service · Performance

Get your Core Web Vitals in the green

LCP, CLS and INP are measured by Google on your real visitors. We find what slows your pages down, fix it in your code and verify the result in the field.

Does any of this sound familiar?

Core Web Vitals rarely degrade all at once: dozens of small causes pile up.

  • "Poor" URLs in Search Console

    The Core Web Vitals report flags your pages red or orange, and you do not know where to start.

  • A slow site on mobile

    The desktop score is fine, but on phones pages take 4, 5, 6 seconds to show up.

  • A layout that jumps

    Banners, images, fonts or ads that push the content around while loading (CLS).

  • Interactions that lag

    Menus, filters or buttons that respond with a delay (INP), especially on modest devices.

  • Plugins and scripts piling up

    Tag manager, chat, A/B testing, widgets: every addition costs milliseconds nobody measures.

  • A score that drops again after every fix

    You have optimised before, but without field measurement the gains do not hold over time.

What you get

  • 01

    A diagnosis based on your real visitors

    CrUX and Search Console field data, completed by lab tests to isolate each cause.

  • 02

    The real causes, not a score

    For every degraded metric: the element, resource or script responsible, template by template.

  • 03

    Fixes delivered in your code

    We implement the optimisations with your team or directly, on WordPress, Shopify, Next.js or custom stacks.

  • 04

    A result verified in the field

    Field metrics tracked for the 3 to 4 weeks after release, the time Search Console needs to reflect the fixes.

What we analyse

The three official metrics, and everything that moves them.

  • LCP - Largest Contentful Paint

    LCP element per template, TTFB, render-blocking resources, images (format, dimensions, priority), fonts, critical CSS.

  • CLS - Cumulative Layout Shift

    Images and iframes without dimensions, font swaps, injected banners, dynamic content.

  • INP - Interaction to Next Paint

    Long tasks on the main thread, third-party scripts, hydration, expensive event handlers.

  • Server & caching

    Response time, server and browser caching, compression, HTTP/2 or HTTP/3, CDN.

  • Third-party scripts

    Tag manager, analytics, chat, ads, A/B testing: the real cost of each script and its loading strategy.

  • Field vs lab data

    CrUX, Search Console and Lighthouse cross-checked so we only fix what your visitors actually experience.

Our method

Measure before, fix, measure after.

  1. 1

    Measure

    CrUX and Search Console field data, Lighthouse tests per page template, on mobile and desktop.

  2. 2

    Diagnose

    Identify the element or script responsible for each degraded metric.

  3. 3

    Prioritise

    Fixes ranked by expected gain and effort, template by template.

  4. 4

    Implement

    Fixes delivered in your code, with your team or by us, tested before release.

  5. 5

    Follow up

    Field metrics verified for 3 to 4 weeks after deployment.

The deliverable

A readable diagnosis and fixes in production - not another report.

  • Diagnosis per template: LCP, CLS, INP with the cause of each degradation
  • List of fixes ranked by expected gain and effort
  • Fixes implemented in your code (or specified for your team)
  • Before / after measurements, in the lab and in the field
  • Recommendations to keep metrics green (performance budget, rules for third-party scripts)
  • Video-call walkthrough with your team

Every fix is documented: your team knows what changed and why.

Where to start?

Free online measurement

Free

LCP, CLS, INP and performance score for one page, mobile or desktop, in a few tens of seconds depending on page size. No account needed.

Measure my page

Core Web Vitals optimization

On quote

Based on the number of templates and your technology. Free first diagnosis within one business day.

  • Field + lab diagnosis
  • Fixes implemented in your code
  • Follow-up after release
Request a diagnosis Answered by an expert, not a salesperson

Frequently asked questions

What exactly are Core Web Vitals?

Three metrics defined by Google to measure the real experience of your visitors: LCP (time to display the largest visible element, good under 2.5 s), CLS (visual stability during loading, good under 0.1) and INP (responsiveness to interactions, good under 200 ms). A page is considered good when 75% of its visits meet these thresholds.

Why is my Lighthouse score good while Search Console rates me "poor"?

Lighthouse is a lab test on a simulated device and connection. Search Console uses field data (CrUX) from your real visitors, often on slower phones and worse networks. Field data is what counts for Google, and it is what we target.

Are Core Web Vitals really a ranking factor?

Yes, since the Page Experience update. The weight is modest compared with content and links, but the indirect effect is significant: a faster site is crawled better, converts better and is abandoned less. On mobile, the difference between 2 and 5 seconds shows directly in the bounce rate.

INP replaced FID: what does that change?

Since March 2024, INP measures the responsiveness of every interaction in the session, not just the first one. Many sites that passed FID fail INP because of third-party scripts and long JavaScript tasks. It is now the metric that fails most often.

Do you work directly in the code?

Yes. We deliver the fixes in your code, together with your team or autonomously, on WordPress, Shopify, Next.js or a custom site. If you prefer, we provide precise specifications for your team to implement.

How long before Search Console reflects the fixes?

CrUX data covers a rolling 28-day window: after release, it usually takes 3 to 4 weeks for the Core Web Vitals report to fully reflect the gains. We track the metrics during that period.

Get your Core Web Vitals in the green

Describe your site: an expert replies within one business day with a first diagnosis and an intervention proposal.

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