The verdict in three sentences
A Core Web Vitals audit costs 1,800 to 4,500 EUR and the follow-on optimisation 3,500 to 9,000 EUR in Berlin in 2026, over a 3 to 5 week timeline. The goal is to move LCP, INP and CLS into Google's green thresholds, which unlocks both SEO and conversion rate. On a B2B store, the expected conversion gain sits between 10 and 25 % with zero extra ad spend.
The three metrics to quantify
Core Web Vitals measure the real user experience. Three indicators matter, each with a precise threshold to be rated "good" by Google.
| Metric | "Good" threshold | Common problem | Optimisation lever |
|---|---|---|---|
| LCP | < 2.5 s | Unoptimised hero image | WebP/AVIF, preload, CDN |
| INP | < 200 ms | Blocking JavaScript | Code splitting, targeted hydration |
| CLS | < 0.1 | Ads/images without dimensions | Reserve space, stable fonts |
| TTFB | < 800 ms | Slow hosting | Server cache, edge |
A red score on even one of these metrics is enough to hurt Google rankings and drive away mobile visitors, often on average connections.
One-off optimisation or performance-first rebuild
The Berlin store owner has two strategies. One-off optimisation fixes the most visible issues on an existing site. A performance-first rebuild reconstructs the technical architecture with speed at the core of the design from the outset.
| Criterion | One-off optimisation | Performance-first rebuild |
|---|---|---|
| 2026 cost | 3,500 - 9,000 EUR | 14,000 - 33,000 EUR |
| Timeline | 3 - 5 weeks | 8 - 14 weeks |
| Achievable LCP | 2 - 2.5 s | < 1.5 s |
| Durability of gain | Medium (1-2 years) | High (3+ years) |
| Conversion impact | +10 to 15 % | +15 to 25 % |
| Project risk | Low | Medium |
For a site whose architecture is still sound, one-off optimisation offers the best cost/benefit ratio. A rebuild is justified only when the technical foundation is obsolete.
Mini case study
Thomas, e-commerce lead at a B2B industrial supplies distributor in Berlin, has a 4.3s LCP and a red INP on mobile. Online revenue is 120,000 EUR/month with a 1.4 % conversion rate. After an optimisation at 7,000 EUR (LCP brought to 1.9s, INP to 150 ms), conversion rises to 1.7 %, i.e. +21 %. That is about 25,000 EUR of additional monthly revenue: the investment pays back in under 10 days.
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FAQ
How much does a Core Web Vitals audit cost in Berlin in 2026?
Between 1,800 and 4,500 EUR depending on depth: a full audit includes field data (CrUX), lab data (Lighthouse) and a costed fix priority list. It is often credited against the optimisation cost if you proceed.
How quickly do results show on Google?
Technical gains are immediate, but Google updates field data (CrUX) over a rolling 28-day window. Expect 4 to 6 weeks to see the full SEO impact.
Is optimisation enough or must I rebuild?
If your architecture is sound, an optimisation at 3,500-9,000 EUR is enough. A rebuild is only justified when the technical foundation durably blocks performance.
What conversion gain can I expect?
On a B2B store, moving all three metrics into the green typically yields +10 to 25 % conversion, especially on mobile traffic and slow connections.
Do I need a maintenance budget afterwards?
Yes, a monthly follow-up of 350 to 700 EUR prevents score regressions each time you add content or tracking.
Let's scope your project. Send us the URL to audit and your current PageSpeed scores; we will quote the optimisation and expected gain. 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.
