century21.fr shows strong AI visibility with an ACRI of 66/100, outperforming 57% of indexed domains. Its server-rendered architecture ensures AI crawlers receive complete HTML on first request, a key advantage for extractability. The 5.9× token bloat ratio falls within the normal range, though there is room to trim navigation, footer, and script overhead. Zero schema blocks puts this site at a disadvantage in knowledge graph and AI-answer pipelines that rely on explicit structured data. The site maintains an open-door policy for AI crawlers — GPTBot, ClaudeBot, and other major agents are all allowed.
🧮 Score Transparency — How is this calculated?
📊 ACRI Sub-Scores (AI Readiness Detail)
century21.fr punches above its weight in AI — AI visibility exceeds Google ranking. This is a competitive moat worth protecting. ACRI measures technical crawler readiness. Read the methodology →
Why century21.fr ranks here
Fastest improvements
- Add basic Organization and WebSite JSON-LD to fix “0 schema blocks” (see Schema Coverage).
- Reduce token bloat (navigation/footer/code) so agents reach your main content faster (see Token Bloat).
- Create an
llms.txtfile so AI crawlers can discover your content structure without heavy crawling. Generate llms.txt → - Run a full entropy audit to find which DOM regions waste the most tokens. Run Entropy Audit →
Traditional SEO
35/100 25 % of Global Score 🟢 High Confidence📝 Title Tag
Optimal range: 30–60 characters for SERP display.
📋 Meta Description
Optimal range: 120–160 characters for snippet control.
🔤 Heading Hierarchy
- ✓ Exactly 1 <h1> tag — found 1
- ✓ Has <h2> headings — found 6
- ✓ <h2> not before <h1>
🔍 Indexability
- ✗ Canonical tag present
- ✓ No noindex directive
- ✓ Meta viewport set
- ✓ HTML lang attribute →
fr - ✗ Hreflang tags
- ✓ Googlebot allowed by robots.txt
🌐 Social / OpenGraph
- ✓ og:title — Agences Immobilières CENTURY 21 : Immobilier et annonces immobilières de vente, d’achat, et de location
- ✓ og:description — Bienvenue chez CENTURY 21, réseau d’agences immobilières qui vous proposent leur expertise que ce soit à la vente, l’achat, la location, la gestion locative et le syndic. Venez confier votre projet immobilier de vente d’appartement ou de maison, nos meilleurs agents immobilier sauront estimer gratuitement la valeur de votre bien et vous prodiguer des conseils. Trouvez ici la meilleure agence qui vous correspondra grâce aux avis de ses clients.
- ✓ og:image — preview
- ✓ twitter:card — summary
📐 How the SEO Pillar score is calculated
SEO Pillar = Title (20 pts) + Meta Desc (20 pts) + Heading Hierarchy (20 pts) + Indexability (20 pts) + Social/OG (20 pts)
Each sub-score is derived from the checks above. Canonical tag, lang attribute, og:image, and a single H1 are the highest-impact items.
AI Readiness / GEO
76/100 40 % of Global Score 🟢 High ConfidenceThis pillar aggregates citation share, hallucination risk, bot access, schema health, and content extractability. The individual diagnostic sections below contribute to this score.
Is AI lying about your brand? This panel measures how likely LLMs are to hallucinate facts when extracting information from your page.
🤖 Bot Access Matrix
📊 Structure & Information Density Docs
🏷️ Schema Health Docs
Schema Coverage Map
📐 AI Efficiency Metrics Docs
Token Bloat Research
Multimodal Readiness
TDM Rights
🔥 Structural Entropy Check Research
🔬 AI-Crawler Simulation
See your website the way AI crawlers do. CSS stripped, structure labeled, content chunked.
Toggle to "AI Agent View" to see what GPTBot, ClaudeBot, and other AI crawlers actually extract from this page.
AI Answer Preview
NEWSee how AI models summarize your site. Left: your actual content. Right: what the LLM extracts and says about you.
The LLM Interpretation
AI-VERIFIEDSEODiff AI analyzed the extracted content of century21.fr and produced this structured business intelligence. Fields marked SEMANTIC VOID indicate information the AI could not find — a critical gap in your site’s machine-readability.
🔧 Tech Stack
Performance & Speed
62/100 20 % of Global Score 🟢 High Confidence⏱️ Time to First Byte
Google considers <200 ms "good". AI crawlers may have even shorter timeouts.
📦 Page Weight
DOM nodes
HTML payload
🗄️ Cache & CDN
- ✓ Cache-Control header →
max-age=900 - ✗ CDN cache status
- ✗ CDN detected
🔬 Tracker Tax
tracker scripts
third-party domains
token overhead
📐 How the Performance Pillar score is calculated
Perf Pillar = TTFB (35 pts) + Page Weight (25 pts) + Cache/CDN (20 pts) + Tracker Tax (20 pts)
TTFB <200 ms = full marks. DOM >3000 or payload >300 KB incurs heavy penalties. Tracker scripts beyond 5 reduce score.
Architecture & Trust
81/100 15 % of Global Score 🟢 High Confidence🗺️ Sitemap & Robots
- ✓ Sitemap declared in robots.txt →
https://www.century21.fr/sitemap.xml - ✓ Googlebot allowed
- ✓ GPTBot allowed
- ✓ ClaudeBot allowed
🔗 Linking
internal links
external links
🔒 Security & Trust
- ✗ HSTS header (Strict-Transport-Security)
- ✗ Content-Security-Policy header
- ✓ HTTP status 200 OK (got 200)
♿ Accessibility Signals
- ✓ HTML lang attribute → fr
- ✓ Meta viewport for mobile
- ✓ Single H1 for screen readers
📐 How the Architecture Pillar score is calculated
Arch Pillar = Sitemap & Robots (30 pts) + Linking (25 pts) + Security (25 pts) + Accessibility (20 pts)
Having a valid sitemap, allowing AI bots, HSTS, and a good internal link count are the highest-impact items.
🏅 AI-Verified Trust Badge
Your site scores 48/100. Reach 80+ to unlock the green "AI-Verified" badge. Fix the issues below to improve your score.
<a href="https://seodiff.io/radar/domains/century21.fr" rel="noopener"><img src="https://seodiff.io/api/v1/badge?domain=century21.fr" alt="AI-Verified by SEODiff" width="280" height="52"></a>
💡 Paste in your site footer, GitHub README, or email signature. Badge updates automatically as your score changes.
� Deep Crawl Analysis 66 pages · Deep-10
| Page | Type | ACRI | Token Bloat | Words | Status |
|---|---|---|---|---|---|
| pricing | 69 | 72.3× | 887 | 💰 Pricing | |
| other | 69 | 64.9× | 960 | ✓ | |
| other | 69 | 59.7× | 986 | ✓ | |
| other | 69 | 62.1× | 1095 | ✓ | |
| other | 69 | 66.7× | 853 | ✓ | |
| other | 69 | 63.6× | 1013 | ✓ | |
| other | 69 | 60.2× | 1031 | ✓ | |
| other | 69 | 62.3× | 1018 | ✓ | |
| other | 69 | 64.2× | 946 | ✓ | |
| other | 69 | 61.9× | 921 | ✓ | |
| other | 69 | 65.6× | 980 | ✓ | |
| other | 69 | 63.5× | 873 | ✓ | |
| other | 69 | 64.0× | 908 | ✓ | |
| other | 69 | 63.1× | 961 | ✓ | |
| other | 69 | 68.2× | 888 | ✓ | |
| other | 69 | 61.8× | 929 | ✓ | |
| other | 69 | 73.2× | 877 | ✓ | |
| other | 69 | 65.5× | 893 | ✓ | |
| pricing | 69 | 62.6× | 908 | 💰 Pricing | |
| other | 69 | 64.2× | 1025 | ✓ |
| Path | Pages | Avg ACRI | Ghost % | Bloat | Top Issue |
|---|---|---|---|---|---|
| /trouver_logement/ | 66 | 69 | 0% | 64.4× | High JS Bloat |
instagram.com
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Scores update automatically each month. Create a free account for on-demand re-crawls (3/month free).
🔌 API Access
Pull this data programmatically. All sub-page metrics are available via our public API.
curl https://seodiff.io/api/v1/deep10/domain/century21.frGet your free API key — 100 requests/month included.
🔗 Similar Sites
Domains with a similar tech stack, industry, and AI readiness profile to century21.fr. Compare side-by-side.
| Domain | ACRI | AI Score | Tech Stack | Token Bloat | Schema | |
|---|---|---|---|---|---|---|
| century21.fr (this site) | 48 | 66 | Custom / Proprietary | 5.9× | 0 | — |
| green-dog.com | 58 | 77 | Custom / Proprietary | 5.4× | 0 | Compare → |
| 98-shop.com | 58 | 76 | Custom / Proprietary | 5.1× | 0 | Compare → |
| seojeong.ac.kr | 58 | 80 | Custom / Proprietary | 4.8× | 0 | Compare → |
| baohohoanglong.com | 58 | 72 | Custom / Proprietary | 4.5× | 0 | Compare → |
| webline.in | 58 | 73 | Custom / Proprietary | 3.8× | 0 | Compare → |
📊 Semantic Share of Voice
How often would an AI cite century21.fr when users ask about topics in this domain's niche? We run entity queries through our 188k-page search index and measure citation probability.
Analyzing citation landscape…
Remediation Patches
COPY-PASTEAuto-generated code fixes tailored to century21.fr. Copy and paste these into your codebase to improve AI visibility. These patches are mathematically proven to increase extraction accuracy →
<script type="application/ld+json">
{
"@context": "https://schema.org",
"@type": "Organization",
"name": "Century21",
"url": "https://century21.fr",
"logo": "https://century21.fr/logo.png",
"sameAs": []
}
</script>
<script type="application/ld+json">
{
"@context": "https://schema.org",
"@type": "WebSite",
"name": "Century21",
"url": "https://century21.fr",
"potentialAction": {
"@type": "SearchAction",
"target": "https://century21.fr/search?q={search_term_string}",
"query-input": "required name=search_term_string"
}
}
</script>
<script type="application/ld+json">
{
"@context": "https://schema.org",
"@type": "FAQPage",
"mainEntity": [
{
"@type": "Question",
"name": "What is Century21?",
"acceptedAnswer": {
"@type": "Answer",
"text": "Add your answer here — describe what Century21 does in 1-2 sentences."
}
},
{
"@type": "Question",
"name": "How does Century21 work?",
"acceptedAnswer": {
"@type": "Answer",
"text": "Explain the key features and how users interact with Century21."
}
}
]
}
</script>
Projected Impact
ROI EST.If you apply the patches above, here's the estimated improvement for century21.fr:
*Estimates based on SEODiff's scoring model. Actual results depend on implementation quality.
📋 Data Export
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All data is generated automatically and updated with each crawl. JSON exports contain scores and metadata only (no copyrighted content).
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