The verdict in three sentences
A B2B site with a mobile LCP above 4.2 s and an INP of 350 ms loses quote requests every week, especially from buyers browsing on a phone between meetings. In Amsterdam, with agency day rates around 850 EUR, budget 2,000 to 4,000 EUR for an audit, then 5,000 to 14,000 EUR of fixes on an existing WordPress site, or 18,000 to 30,000 EUR for a Next.js rebuild if the theme cannot be saved. The 2026 gain we observe is 18 to 35 % more forms sent once LCP drops below 2.5 s.
Reading your Core Web Vitals correctly
Google measures three metrics on real visits (CrUX data, rolling 28 days): LCP (rendering of the largest visible element), INP (responsiveness to clicks, which replaced FID in 2024) and CLS (visual stability). A lab Lighthouse score is not enough: the 75th percentile of real visitors is what counts.
| Metric | Good | Needs improvement | Poor | Typical B2B manufacturer |
|---|---|---|---|---|
| Mobile LCP | under 2.5 s | 2.5 to 4 s | over 4 s | 4.2 to 5.5 s |
| INP | under 200 ms | 200 to 500 ms | over 500 ms | 300 to 400 ms |
| CLS | under 0.1 | 0.1 to 0.25 | over 0.25 | 0.12 to 0.3 |
| Home page weight | under 1.5 MB | 1.5 to 3 MB | over 3 MB | 4 to 7 MB |
| Third-party scripts | under 5 | 5 to 10 | over 10 | 12 to 18 |
Usual culprits on industrial sites: a background video on the home page, 2 MB PNG product images, a heavy page builder (Elementor, Divi, WPBakery), and chat, CRM, maps and ad pixels loaded without priority.
2026 rates in Amsterdam: three levels of intervention
| Intervention | Scope | Price (ex. VAT) | Timeline | Expected LCP gain |
|---|---|---|---|---|
| Technical audit | CrUX, Lighthouse, WebPageTest, prioritised plan | 2,000 to 4,000 EUR | 1 to 2 weeks | none, diagnosis |
| Light fixes | AVIF images, caching, CDN, font preload | 5,000 to 7,500 EUR | 2 weeks | 1 to 1.5 s |
| Heavy fixes | Theme cleanup, deferred scripts, critical CSS | 8,500 to 14,000 EUR | 3 to 5 weeks | 1.5 to 2.5 s |
| Next.js rebuild | New front end, headless CMS, content migrated | 18,000 to 30,000 EUR | 8 to 12 weeks | target LCP under 1.8 s |
| Monthly monitoring | CrUX tracking, alerts, tweaks | 250 to 500 EUR/month | ongoing | maintenance |
For reference, the same work in Toulouse costs 1,200 to 2,500 EUR for the audit, 3,000 to 9,000 EUR for fixes and 12,000 to 20,000 EUR for a rebuild, which is the grid Kolonell applies to Dutch clients working with us remotely. Decision rule: if the audit shows more than 40 % of page weight comes from the page builder and plugins, fixes hit a ceiling and a rebuild is cheaper over 3 years.
Mini case study
Sanne, marketing manager at an 80-person precision engineering firm near Amsterdam, receives 45 quote requests a month through the website, 60 % of them on mobile. Mobile LCP is 4.4 s. After a 3,000 EUR audit and 11,000 EUR of heavy fixes, LCP drops to 2.1 s and INP to 170 ms. Requests rise to 56 a month, up 24 %. With an 8 % conversion rate and an average margin of 7,000 EUR per order, the 11 extra requests mean about 0.9 orders a month, roughly 6,200 EUR of monthly margin. The 14,000 EUR investment pays back in under three months.
FAQ
Need a professional website?
Kolonell builds websites that attract clients, optimized for the Sénégalese market. Free quote in 2 minutes.
How long until Search Console shows the effect?
CrUX data uses a rolling 28-day window, so expect 4 to 6 weeks after the fixes before the Core Web Vitals report turns green.
Do Core Web Vitals improve rankings?
They are a secondary ranking signal, real when content is equal. The main effect is conversion: 18 to 35 % more forms sent is common once LCP drops under 2.5 s.
Can we keep Elementor or Divi?
Often yes, with fixes at 8,500 to 14,000 EUR in Amsterdam. If LCP stays above 3 s after cleanup, a rebuild becomes the rational choice.
Why is INP so poor on B2B sites?
Third-party scripts: chat, CRM, maps, analytics. Deferring or removing 5 to 8 scripts often brings INP from 350 ms to under 200 ms.
Is monthly monitoring necessary?
It prevents regressions: one new video or ad pixel can add 1 s of LCP. Budget 250 to 500 EUR a month locally, or 150 to 350 EUR with a remote studio.
Let's scope your project. Send us your site URL and request volumes, and we will price the audit and fixes, or the rebuild if it is the better option. Detailed quote within 48 h. WhatsApp +221 77 596 93 33.
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.
