What does StackOptic analyze?

StackOptic runs 18 analysis modules on any public website from a single URL. It detects 7,000+ technologies (CMS, frameworks, analytics, payments, CDN, hosting), evaluates SSL certificates and HTTP security headers with grades from A+ to F, measures Core Web Vitals (LCP, CLS, TBT, FCP), audits SEO meta tags and structured data, checks email security (SPF, DKIM, DMARC), analyzes AI & LLM readiness including bot access and llms.txt validation, extracts color palettes and typography, estimates carbon footprint, and generates permanent shareable reports.

Does it work on sites behind Cloudflare or bot protection?

Yes. StackOptic uses a real browser engine that loads pages exactly like a human visitor — executing JavaScript, rendering CSS, and handling redirects. This allows it to bypass Cloudflare, LiteSpeed, Sucuri, and other bot protection systems where traditional crawlers and HTTP-only tools fail.

What do I get on the free plan?

The free plan includes 5 analyses per day with access to all 18 modules, full scores, technology detection, and security grades. Every report is permanently accessible via a unique shareable URL — no login required to view. No credit card needed. AI-powered insights, re-analysis, PDF/JSON export, and comparison features are available on Pro ($24/mo) and Agency ($99/mo) plans.

What is AI & LLM readiness analysis?

This module evaluates how visible and citable your website is to AI search engines like ChatGPT, Perplexity, Google AI Overviews, and Claude. It audits access permissions for 8 major AI bots, validates llms.txt and llms-full.txt files, scores citation-ready content structure, and analyzes structured data (JSON-LD) for GEO readiness — helping you rank in the next generation of search.

How long does an analysis take?

Most analyses complete in under 10 seconds. StackOptic runs all 18 modules in parallel using a real browser session, so you get technology detection, security audit, performance metrics, SEO analysis, and AI readiness scoring simultaneously.

How accurate are the results?

Detection is based on real browser execution — DOM inspection, JavaScript runtime analysis, HTTP headers, and DNS records. With 7,000+ technology signatures and Lighthouse-calibrated performance scoring, StackOptic achieves high accuracy for mainstream technologies.

What security checks are performed?

The security module evaluates SSL/TLS certificates, 12+ HTTP security headers (HSTS, CSP, X-Frame-Options, Permissions-Policy, Referrer-Policy), HTTPS enforcement, and email authentication (SPF, DKIM, DMARC). Each site receives a letter grade from A+ to F with specific remediation steps.

Do you store the websites I analyze?

StackOptic only stores publicly available information that any visitor to a website would see — HTML content, HTTP headers, DNS records, and screenshots. We do not access private data, log in to websites, or perform any intrusive testing.

Back to Search

sfr.fr

https://sfr.fr· First analyzed 16 Feb 2026· Updated 16 Feb 2026

Export

sfr.fr

Sponsored

Hosting Provider

SFR SA

IP Address

80.125.163.172

Server Location

🇫🇷 Paris, France

ASN

AS15557

Organization

SFR SA

Server

SFR Reverse Proxy

Nameservers

ns2pub.sfr.fr.ns1pub.sfr.fr.

Performance

Page Speed

48 requests

Image Optimization

Lazy LoadWebPResponsive

0–49

50–89

90–100

Architecture Stack

Monolithic

⚙️ SSR

Infrastructure

Hosting

SFR SA

SEO Analysis

B72/100

sfr.frsfr.fr

SFR | Internet Fibre et ADSL, Forfaits 5G, Téléphone, TV

No description available for this page.

Title Length56 chars

Recommended: 50-60 chars

Description Length0 chars

Recommended: 120-160 chars

Issues (2)

• Missing meta description - important for click-through rates
• Many images missing alt text (11/16)

2 issues found

Upgrade to view details

Crawlability

Sitemap

Type: standard

robots.txt

88 rules

Sitemap reference found

Sponsored

Security Score

36%Critical

Interactive

HTTPS

No WAF

63d

Certificate Details

Type

Organization Validated (OV)

Certificate Authority

DigiCert Inc

Key Algorithm

RSA (2048 bit)

Signature

SHA-256 with RSA

TLS Version

TLSv1.3

HTTP Protocol

HTTP/1.1

Valid From

20.03.2025

Valid Until

20.04.2026

OCSP Stapling

Enabled

Subject Alternative Names (2)

www.sfr.frsfr.fr

SHA-256 Fingerprint

BE:18:EF:FD:73:91:AC:CD:1E:91:C7:4E:B6:5E:6F:71:F3:11:3C:D5...

Top Recommendations

Security recommendation preview

Upgrade to view recommendations

Upgrade to view header details

HTTP Headers

Developer Console

cache-control

🟡 240s(max-age=240, public)

content-encoding

⚡ Brotli(br)

content-language

fr-FR

content-type

text/html;charset=UTF-8

date

Mon, 16 Feb 2026 20:19:06 GMT

expires

Mon, 16 Feb 2026 20:23:06 GMT

Good Warning Issue

Email Infrastructure

Custom Mail Server

Score

SPF

DKIM

DMARC

DMARC Policy

Reject (Strictest)

MX Records (1)

smtp-in.sfr.fr

Domain Information

sfr.fr

Domain Age

29y 7m

Created

22.07.1996

Expires

18.11.2026

Last Updated

31.12.2025

Registrar

SFR

DNSSEC

Not Enabled

Privacy & Compliance

Cookie Consent Banner

GDPR Indicators

Cookie consent banner detected

Typography & Readability

SFR-Bold + Arial

46/100

Readability

/30

40/40

24px · LH 1.50

Hierarchy

/20

8/25

1.33x ratio

WCAG

/25

5/15

Contrast: undefined

Performance

/25

10/20

4 fonts

Heading Font

SFR-Bold

Sans32px

Body Font

Arial

Sans24px

Contrast Ratio

Reading Comfort

~44 CPL

Needs attention

32px

24px

✅ Excellent readability: 24px body text is ideal for all devices.

✅ Optimal line spacing: 1.50 ratio ensures comfortable reading.

⚠️ Weak hierarchy: Headlines should be at least 2x body size for clear visual structure.

⚠️ Risky: Text appears on background images without overlay protection.

⚠️ Cramped layout: 46 elements lack adequate spacing.

Buy on MyFonts

Business & Marketing Stack

3 Tools Detected

Advanced

Behavior Analytics

Google Tag ManagerFree

Google AnalyticsFree

User behavior and product analytics

Privacy & Cookies

Quantcast ChoiceMid-Market

Cookie consent and privacy compliance tools

Sponsored

Scripts & Styles

13 Resources

Scripts

Styles

Async

Defer

Top Script Sources

static.s-sfr.fr(6)genki.sfr.fr(3)sfr.fr(1)

Website Identity

Facebook X (Twitter)YouTube

Sponsored

Last analyzed: 16 Feb 2026 at 20:19

Historical Analysis & Change Tracking