Should you block countries with slow connections to boost your Core Web Vitals?

Why do some sites block entire geographies?

The initial logic seems appealing: since the Core Web Vitals are measured through real-world data from the Chrome User Experience Report (CrUX), blocking users with poor connections should mechanically improve aggregated scores. Geographical areas with inadequate network infrastructure — certain regions of Africa, Southeast Asia, or Latin America — statistically pull the metrics down.

This approach reveals a fundamental misunderstanding of what Google values. The Core Web Vitals are not an end in themselves, but a proxy for measuring real user experience. Optimizing a metric by deliberately excluding part of your audience is confusing the thermometer with the illness.

What happens when an entire country is blocked?

Determined users won’t passively accept a geographic block. They activate a VPN or go through a proxy to bypass the restriction. The paradox: these tools add an additional layer of network latency, further degrading load times.

The result? You end up with CrUX metrics worse than before the block, while losing the trust of a part of your audience. Not to mention the negative impact on your reputation and conversion rate if those geographical areas represented a viable business segment.

What are the real levers to improve Core Web Vitals?

Google implicitly reminds us that optimizing the Core Web Vitals should come from real technical improvements, not statistical tricks. This means reducing the weight of resources, optimizing critical rendering, eliminating layout shifts, and improving Time to First Byte.

The real performance benefits all your users, regardless of their location. It’s this universal approach that Google values, not an optimization that arbitrarily excludes audience segments to flatter an algorithm.

• The Core Web Vitals are a user experience indicator, not an isolated goal to achieve by any means necessary
• Blocking countries with slow connections paradoxically degrades metrics through the use of VPNs/proxies
• Real technical optimization (weight, rendering, TTFB) remains the only legitimate and sustainable lever
• A geographic blocking strategy harms reputation and business without measurable SEO gain
• Google detects and may penalize attempts to distort CrUX data

Is this statement consistent with real-world observations?

Absolutely. Since 2021, there have been sporadic attempts at SEO geo-blocking on international e-commerce sites or content aggregators. The results are consistently disappointing: either the CrUX metrics do not improve (due to the massive use of VPNs), or Google downgrades the site for user data manipulation.

The consistency with Google's product philosophy is total. The Chrome team maintaining CrUX has always emphasized the integrity of real-world data. Any attempt to skew the sample — whether through cloaking, geo-blocking, or user-agent detection — directly contradicts this objective.

What nuances should be added to this position?

Splitt's statement remains deliberately generic. It does not distinguish between legitimate commercial blocking (legal constraints, distribution rights) and purely opportunistic blocking aimed at manipulating Core Web Vitals. In the former case, no one will blame you for adhering to the law.

Moreover, Google provides no quantitative data on the proportion of users who actually bypass geo-blocks via VPN. [To be checked]: this claim likely relies on internal Chrome observations, but the scale of the phenomenon varies significantly by geographical areas and content types.

In which cases could this rule be nuanced?

If your site does not objectively target certain geographical areas — for instance, a local B2B service in a regional language — it is legitimate not to invest in technical optimization for connections you are not commercially targeting. This is not geo-blocking; it's a rational prioritization of technical resources.

However, caution: even in this case, do not actively block access. Simply leave the site accessible with its current performance. The difference is crucial: a slow yet accessible site does not trigger the same negative signals as a deliberate block that could be interpreted as an attempt to manipulate.

What should you do concretely to improve Core Web Vitals?

The answer boils down to one word: real technical optimization. Reduce image sizes using modern formats (WebP, AVIF), implement intelligent lazy-loading, eliminate render-blocking resources, optimize your Critical Rendering Path. These improvements benefit all of your users, regardless of their location.

Invest in a high-performing CDN with points of presence in the geographical areas you are commercially targeting. If your CrUX metrics are poor in Southeast Asia but that region represents 15% of your revenue, the issue is not your users' connections — it's your server infrastructure that is lacking.

What critical mistakes should you absolutely avoid?

Don’t fall into the trap of single-metric optimization. The Core Web Vitals are one factor among hundreds in Google's algorithm. A site that shows perfect scores but offers mediocre content, inconsistent architecture, or dubious link strategies will never rank well.

Also, avoid any form of geographic cloaking: serving a light version of the site only to IPs identified as coming from slow connection areas. Google detects these practices and can impose severe manual penalties. The integrity of CrUX data is a topic on which the Search Quality team does not compromise.

How can you verify that your strategy aligns with Google’s recommendations?

Analyze your CrUX data by geography via the PageSpeed Insights API or the Chrome UX Report on BigQuery. If certain areas show catastrophic metrics, dig into the technical causes: server latency, absence of local CDN, excessive resource weight. Never assume that the problem lies solely with the user connection.

Test your site using slow connection simulation tools (Chrome DevTools Network Throttling, WebPageTest with 3G/4G profiles). If your site is unusable on a 3G connection, the problem is not the connection — it’s your front-end that requires a deep technical overhaul.

• Audit your Core Web Vitals by geography using the CrUX API or BigQuery
• Identify the real technical causes: TTFB, resource weight, absence of local CDN
• Eliminate any opportunistic geo-blocking aimed solely at manipulating metrics
• Invest in universal front-end optimization: images, lazy-loading, Critical CSS
• Ensure your CDN effectively covers your target geographical areas
• Test regularly on simulated slow connections to validate the actual experience