The verdict in three sentences
When a B2B website shows an LCP of 5.1 s and an INP of 380 ms on mobile, the reflex of a full redesign at EUR 25,000 excl. VAT is not always right. A Core Web Vitals audit priced at EUR 1,500 to 4,000 excl. VAT tells you within 2 to 3 weeks whether targeted fixes at EUR 3,000 to 9,000 are enough to get back to green. In most cases where design and site structure remain relevant, optimisation delivers 10 to 25% more form conversions, in 3 to 6 weeks overall.
Reading the numbers: where your site stands against Google thresholds
Google assesses three metrics on real visitor data (the CrUX report) at the 75th percentile. A business services website in Amsterdam is often viewed on mobile by decision makers on the move, between meetings: that is where the gaps cost the most.
| Metric | Your site (mobile) | Google "good" threshold | Common cause |
|---|---|---|---|
| LCP (main content display) | 5.1 s | 2.5 s or less | 1.8 MB hero image, font not preloaded |
| INP (responsiveness) | 380 ms | 200 ms or less | Third-party scripts, chat, tag manager |
| CLS (visual stability) | 0.18 | 0.1 or less | Cookie banner, images without dimensions |
| Home page weight | 4.6 MB | Under 1.5 MB targeted | Videos and carousels |
| Third-party scripts | 14 | 5 to 7 targeted | Stacked marketing tools |
| TTFB | 1.1 s | 0.8 s or less | Shared hosting, no caching |
What a serious audit includes, and what it costs
A useful audit goes beyond a PageSpeed score. It cross-checks field data (CrUX, Search Console) with profiling of the pages that generate leads: home, service pages, contact form, white papers. The deliverable is a prioritised list of fixes, each with its estimated gain and cost.
| Audit package | 2026 price (EUR excl. VAT) | Scope | Timeline |
|---|---|---|---|
| Express diagnosis | 1,500 to 2,000 | 5 templates, prioritised report | 1 to 2 weeks |
| Full audit | 2,500 to 4,000 | 10 to 15 templates, third-party scripts, hosting | 2 to 3 weeks |
| Targeted fixes | 3,000 to 9,000 | Images, fonts, scripts, caching, CLS | 2 to 4 weeks |
| Full redesign | About 25,000 | Design, content, technology | 4 to 6 months |
| Monthly monitoring | 150 to 300 per month | CrUX monitoring, alerts, report | Ongoing |
Optimise or redesign: the decision grid
The question is not "is the site slow?" but "does the slowness come from the foundation or from added layers?". Images, fonts, third-party scripts and missing caching can be fixed without rebuilding. A heavy theme with a page builder generating 3,000 DOM elements per page, however, hits a ceiling quickly.
| Observed situation | Recommendation | Indicative budget |
|---|---|---|
| Recent design (under 4 years), image and script issues | Targeted fixes | EUR 3,000 to 6,000 |
| Slow shared hosting, TTFB above 1 s | Hosting migration + caching | EUR 1,500 to 3,000 |
| Heavy page builder, DOM above 2,500 nodes | Rebuild of key templates | EUR 9,000 to 15,000 |
| Outdated content, changed positioning | Full redesign | EUR 25,000 and up |
| Mobile score already fine, weak conversions | UX and content work, not performance | Variable |
Mini case study
Sanne, marketing director of an Amsterdam business services company (facility management, 320 employees), receives 140 contact requests per month from 24,000 visits, a 0.58% conversion rate. She orders a full audit at EUR 3,200 excl. VAT, then fixes at EUR 6,500 excl. VAT: image compression, removal of 6 third-party scripts, font preloading, server caching. LCP drops to 2.1 s and INP to 170 ms. Conversions rise by 18%, or 25 more requests per month. With an 8% signing rate and an average contract worth EUR 14,000 in annual revenue, that means 2 new contracts per month. The total budget of EUR 9,700 is covered by the first signed contract, and the EUR 25,000 redesign is pushed back by 2 years.
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FAQ
How much does a Core Web Vitals audit cost in Amsterdam in 2026?
Allow EUR 1,500 to 2,000 excl. VAT for an express diagnosis of 5 templates and EUR 2,500 to 4,000 excl. VAT for a full audit. Timelines run 1 to 3 weeks depending on scope.
Are conversion gains guaranteed?
No, these are 2026 orders of magnitude observed on B2B sites: 10 to 25% on forms when LCP gets back under 2.5 s. The gain depends on the share of mobile traffic, often 45 to 60%.
Do we need an in-house developer to apply the fixes?
Not necessarily: targeted fixes are delivered turnkey for EUR 3,000 to 9,000 excl. VAT. Your team simply confirms which marketing scripts to keep.
How long before Google reflects the change?
CrUX data is computed over a rolling 28 days. Allow 4 to 6 weeks after release to see the Search Console report turn green.
Is monthly monitoring worth it?
Yes if several people add content or tools: a single badly configured chat script can add 150 ms of INP. Monitoring costs EUR 150 to 300 per month with alerts.
Let's scope your project. Send us your website URL and lead targets: we will tell you whether optimisation is enough or a redesign is justified, with budget and timeline. Detailed quote within 48 h. WhatsApp +221 77 596 93 33 or request a quote.
Mohamed Bah
Fondateur, Kolonell
Passionate about digital and entrepreneurship in Africa, Mohamed has been helping Sénégalese businesses with their digital transformation since 2020. Founder of Kolonell, he believes every SME deserves a professional and accessible online présence.
