Core Web Vitals for business owners
Core Web Vitals are three measurements Google takes of your pages on real visitors' devices. Getting them into the green costs EUR 100-300 a month as small fixes under a Care plan, EUR 450-750 as a one-off inside an SEO foundation, or EUR 900-1.500 at step 02 to EUR 1.500-3.500 at step 03 when the front end is the cause and has to be rebuilt.
The three have engineering names: Largest Contentful Paint, Interaction to Next Paint and Cumulative Layout Shift. What they measure is not complicated, and each one maps onto something a visitor feels.
Largest Contentful Paint: how long the page looks empty
This one watches for the biggest thing on the screen, usually a headline or a hero image, and records when it appears. Until then the visitor is looking at a blank rectangle with nothing on it.
It fails when the hero image is far larger than the screen showing it, when fonts and stylesheets must finish downloading before any text is allowed to appear, or when the server is slow to answer at all.
Commercially it decides whether a visit happens. Someone who taps a search result or an ad and sees nothing has no reason to stay, and if the click came from an ad, you paid for a visitor who never saw the page.
Interaction to Next Paint: what happens when someone taps
This measures the gap between a tap or a click and the screen visibly responding. Not the whole action finishing, just the page acknowledging that a person touched it.
It fails when too much JavaScript is running at once: third-party scripts, tracking, a page builder's own code, a heavy cookie banner. The browser is busy with all of that and the tap waits its turn.
This is the measurement that matters on the parts of a site that bring in money: a booking form, a filter on a listing, a quote calculator, or a checkout on a step 04 build. A button that does not react gets tapped again, and a form that feels broken gets abandoned.
Cumulative Layout Shift: the page moving under a thumb
This one adds up how much the content jumps while the page loads. An image arrives without its dimensions declared and pushes the paragraph down, a banner is injected at the top and shoves everything along, a font swaps in and the headline re-wraps.
It fails for boring reasons, and boring reasons are cheap to fix: declare image dimensions, reserve space for anything that loads late, load fonts so they do not reflow the text.
Commercially it is the rudest of the three. A visitor reaches for a button, the layout moves, and they tap the wrong thing. On a phone, halfway through a form, that is a lost enquiry and a visitor who now thinks the business is careless.
Where to read your own numbers
There are two places, and they do not always agree. Google Search Console reports the three measurements from real visits, grouped by type of page. PageSpeed Insights tests a single page on demand and gives it a score.
The Search Console report is the one Google uses, because it comes from real phones on real connections. The on-demand test is a diagnostic: it lists what is heavy on the page. Read it as a list of causes, not as a grade.
What each measurement points to
| Measurement | What the visitor feels | Cause | Where the fix sits |
|---|---|---|---|
| Largest Contentful Paint | A blank screen, then everything at once | Oversized hero image, blocking fonts and stylesheets, slow server response | Care fixes, SEO foundation, or a rebuild at step 02 or step 03 |
| Interaction to Next Paint | Taps do nothing, so they get repeated | Too much JavaScript, third-party scripts, page builder code | Care fixes, or step 04 when the slow part sits behind a login or in a dashboard |
| Cumulative Layout Shift | Content jumps and the wrong button gets tapped | Images without dimensions, injected banners, late fonts | Small fixes under Care |
What it costs to move them
- Small fixes, Care, EUR 100-300 a month. Images, scripts, fonts, caching and dimensions, handled alongside updates, monitoring and backups.
- One-off pass, SEO foundation, EUR 450-750. The speed work sits next to Search Console, analytics, indexation, technical hygiene, titles and internal links, and ends with a 3-6 month plan.
- Rebuild, step 02 or step 03. EUR 900-1.500 for 2-3 pages in 2-3 weeks, or EUR 1.500-3.500 for 4-7 pages in 3-6 weeks. This is the answer when the thing generating the page is the thing failing the measurement.
- Behind a login, step 04, EUR 3.500-7.500. Over 6-12 weeks, when the slow part is a dashboard, an API, a CRM connection or payments.
Of those, only Care continues monthly. SEO growth at EUR 500-800 a month is the other ongoing option, if you add it later. The SEO foundation is paid once. A fixed quote always follows scoping. You own the code, the repository and the database, and hosting is agreed per project. The full list is on the packages page.
When these three are not your problem
If Search Console shows your pages getting hardly any impressions, the three measurements are not what is holding you back. Indexation and a lack of links to your site come first, and no amount of green makes an unfound page perform.
If the report already passes, leave it alone. There is no extra credit for being further inside the green, and the money does more on a page that answers a question your buyers actually ask. If one page fails and nobody lands on it, fix the page they do land on instead.
Some of it costs nothing. Compressing a hero image, deleting a chat widget nobody answers, removing a second analytics tool: those are the same fixes we would invoice for, done by you.
Questions worth asking first
Does passing Core Web Vitals make me rank higher?
It is one input among many. When two pages answer a question equally well, the one that is pleasant to use has the edge. It will not lift a page that nothing links to or that does not answer the question. The dependable return is on the visitors who already arrive.
My test score is poor, but the site feels fast to me.
You are probably checking on a laptop, on office wifi, with the site already cached in your browser. Your visitors are on phones, on mobile data, arriving for the first time. Trust the Search Console report over your own impression.
Can the measurements be fixed without redesigning the site?
Yes, when the cause is images, fonts, third-party scripts or caching, which is a Care-sized job or part of an SEO foundation. No, when the cause is the theme or page builder generating the page, because the weight comes back with every update. Testing tells you which one you have before anything is quoted.
Do the sites you build pass?
They are built to. Images are sized before they ship, fonts come from your own domain, JavaScript is limited to what the page needs, and space is reserved for anything that loads late. Every build is measured before launch, from a single-page landing at EUR 600-900 upwards. The technical side is on the Next.js development page.
To find out which of the three your site fails and which step the fix belongs to, send the URL through the contact form.
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