The verdict in three sentences
A slow B2B website loses Google rankings and leads, even when its content beats the competition. A Core Web Vitals audit priced at EUR 1,200 to 3,500 excl. VAT pinpoints the exact causes, then a fix budget of EUR 3,000 to 12,000 brings the site under Google's thresholds. The expected return is an 8 to 15% lift in form conversions, often paid back in under six months.
What a Core Web Vitals audit actually measures
Google scores page experience using three metrics collected from real Chrome users (CrUX data), at the 75th percentile. A marketing manager in Amsterdam watching rankings slip against faster competitors first needs to know which metric is hurting, page by page.
| Metric | What it measures | "Good" threshold 2026 | "Poor" threshold | Common causes on B2B sites |
|---|---|---|---|---|
| LCP (Largest Contentful Paint) | Rendering of the largest visible element | under 2.5 s | over 4 s | Uncompressed hero image, slow server, blocking font |
| INP (Interaction to Next Paint) | Responsiveness after a click | under 200 ms | over 500 ms | Third-party scripts (chat, tag manager, CRM), heavy JavaScript |
| CLS (Cumulative Layout Shift) | Visual stability | under 0.1 | over 0.25 | Cookie banner, images without dimensions, ads |
| TTFB (diagnostic metric) | Server response time | under 0.8 s | over 1.8 s | Shared hosting, no caching, overloaded CMS |
| Mobile page weight | Data transferred | under 1.5 MB | over 4 MB | Autoplay videos, carousels, unused libraries |
| Third-party requests | Number of external domains | fewer than 10 | more than 25 | Ad pixels, widgets, A/B testing tools |
A serious audit combines field data (CrUX, Search Console) with lab tests (Lighthouse, WebPageTest) across the 10 to 30 page templates that drive traffic: home, service pages, industry pages, articles, contact forms.
2026 pricing: audit, fixes and monitoring
Price gaps come from the number of templates analysed, the stack (WordPress, Drupal, Next.js, headless) and the depth of the deliverable. These are 2026 ballpark figures for a B2B site of 50 to 500 pages.
| Service | Scope | Price excl. VAT 2026 | Lead time | Deliverable |
|---|---|---|---|---|
| Express audit | 5 to 10 templates, Lighthouse + CrUX | EUR 1,200 to 1,800 | 5 business days | 15-page report, top 10 actions |
| Full audit | 15 to 30 templates, third-party script analysis | EUR 2,200 to 3,500 | 10 business days | Prioritised report, effort estimate per action |
| Light fixes | Images, caching, fonts, CLS | EUR 3,000 to 5,000 | 2 to 3 weeks | Before/after measured gains |
| Deep fixes | Theme rebuild, JavaScript, hosting | EUR 6,000 to 12,000 | 4 to 8 weeks | Site under thresholds on 90% of URLs |
| Monthly monitoring | Alerts, monthly report | EUR 150 to 400 per month | Ongoing | RUM dashboard |
| Hosting migration | CDN + dedicated server | EUR 800 to 2,500 | 1 to 2 weeks | TTFB cut by 2 to 4x |
A full audit report is delivered within 10 business days. Budget the fixes right after, otherwise the audit stays a document with no impact.
The gains to expect, in numbers
The direct SEO benefit is real but moderate: Core Web Vitals mostly break ties between pages of similar relevance. The most measurable gain is conversion. On B2B sites we have optimised, moving LCP from 4.2 s to 2.1 s comes with an average of 8 to 15% more form submissions, because mobile visitors abandon less before the form appears. Mobile bounce rate usually drops by 10 to 20 points.
Mini case study
Sarah, marketing manager at an engineering consultancy in Amsterdam, gets 14,000 visits a month and 70 contact requests (0.5% rate). Her mobile LCP is 4.6 s and her INP 380 ms because of three third-party scripts.
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Kolonell builds websites that attract clients, optimized for the Sénégalese market. Free quote in 2 minutes.
- Full audit: EUR 2,800 excl. VAT. Deep fixes: EUR 8,500. Total: EUR 11,300.
- After the fixes, LCP is 2.2 s and INP 160 ms. Conversion rises 12%: 70 becomes 78 requests a month, or 96 more leads a year.
- With 5% of leads signed and an average deal of EUR 18,000, that is about 4.8 contracts, or EUR 86,000 in additional revenue. The project pays for itself with the first won contract.
FAQ
How much does a Core Web Vitals audit cost in 2026?
Expect EUR 1,200 to 1,800 excl. VAT for an express audit and EUR 2,200 to 3,500 for a full audit of 15 to 30 templates. The full report is delivered within 10 business days.
Do I need to rebuild the whole site to pass the thresholds?
Rarely. In 70% of cases, targeted fixes at EUR 3,000 to 5,000 (images, caching, fonts, third-party scripts) are enough to bring LCP under 2.5 s. A rebuild is justified when the theme or CMS blocks any optimisation.
How long before Search Console shows the effect?
CrUX data is computed over a rolling 28 days. Allow 4 to 6 weeks after release for the report to turn green.
Is INP harder to fix than LCP?
Yes, because it depends on JavaScript and third-party scripts. Removing or deferring 2 or 3 rarely used marketing tools often saves 150 to 250 ms of INP.
What conversion gain should I really expect?
The 2026 ballpark is 8 to 15% more form submissions for a site moving from "poor" to "good". The gain is stronger when over 50% of traffic is mobile.
Let's scope your project. We audit your key templates, price every fix and hand you a budgeted action plan, from EUR 1,200 for the audit to EUR 12,000 for a full remediation. 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.
