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

ctdo.de

https://ctdo.de· First analyzed 18 Feb 2026· Updated 18 Feb 2026

Export

ctdo.de

Sponsored

Hosting Provider

Chaostreff Dortmund e.V.

IP Address

195.160.168.3

Server Location

🇩🇪 Dortmund, Germany

ASN

AS197782

Organization

Chaostreff Dortmund e.V.

Nameservers

oxygen.ns.hetzner.com.hydrogen.ns.hetzner.com.helium.ns.hetzner.de.

Performance

Page Speed

1.1 MB

52 requests

Image Optimization

Lazy LoadResponsive

0–49

50–89

90–100

Architecture Stack

Headless

⚙️ SSR

Decoupled

API

Data Source

Headless CMS

Strapi

Infrastructure

Hosting

Chaostreff Dortmund e.V.

Detected API Sources

https://status.ctdo.de/api/sim...

Technology Stack

9 Technologies Detected

Plugins

Events Manager Osm Wp Fullcalendar

Libraries

CSS Frameworks

Languages

SEO Analysis

D50/100

ctdo.dectdo.de

Chaostreff Dortmund e.V. – Hackerspace und Raum für Kreativität in ...

No description available for this page.

Title truncated.

Title Length75 chars

Recommended: 50-60 chars

Description Length0 chars

Recommended: 120-160 chars

Issues (1)

• Missing meta description - important for click-through rates

7 issues found

Upgrade to view details

Crawlability

Sitemap

Type: index

7 URLs

robots.txt

4 rules

Sitemap reference found

Sponsored

Security Score

36%Critical

Interactive

HTTPS

No WAF

89d

Certificate Details

Type

Domain Validated (DV)

Certificate Authority

Let's Encrypt

Key Algorithm

RSA (2048 bit)

Signature

SHA-256 with RSA

TLS Version

TLSv1.3

HTTP Protocol

HTTP/2

Valid From

17.02.2026

Valid Until

18.05.2026

Subject Alternative Names (8)

chaostreff-dortmund.dectdo.dedortmund.ccc.dedortmund.chaostreff.defablab-dortmund.derepaircafe-dortmund.dewww.chaostreff-dortmund.dewww.ctdo.de

SHA-256 Fingerprint

3B:06:A6:BC:74:0D:C2:97:48:59:12:9E:00:8B:EA:E5:6F:E9:98:B1...

Top Recommendations

Security recommendation preview

Upgrade to view recommendations

Upgrade to view header details

HTTP Headers

Developer Console

content-encoding

📦 Gzip(gzip)

content-length

46368

content-type

text/html; charset=UTF-8

date

Wed, 18 Feb 2026 06:03:11 GMT

link

<https://www.chaostreff-dortmund.de/wp-json/>; rel="https://...

strict-transport-security

max-age=2592000

Good Warning Issue

Email Infrastructure

Custom Mail Server

Score

SPF

DKIM

DMARC

DMARC Policy

Reject (Strictest)

MX Records (1)

mail.chaostreff-dortmund.de

Domain Information

ctdo.de

Last Updated

19.08.2022

DNSSEC

Not Enabled

Privacy & Compliance

Cookie Consent Banner

GDPR Indicators

Typography & Readability

Arial

85/100

Readability

/30

40/40

16px · LH 1.75

Hierarchy

/20

15/25

1.25x ratio

WCAG

/25

15/15

Contrast: undefined

Performance

/25

20/20

System fonts

Heading Font

Arial

Sans20px

Body Font

Arial

Sans16px

Contrast Ratio

Reading Comfort

~36 CPL

Needs attention

20px

26px

16px

✅ Excellent readability: 16px body text is ideal for all devices.

✅ Optimal line spacing: 1.75 ratio ensures comfortable reading.

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

✅ Excellent performance: System fonts eliminate font loading delays (better LCP).

✅ Consistent design: Single font family with weight variations is a modern best practice.

✅ Protected text on images: Using text-shadow for readability.

Business & Marketing Stack

1 Tools Detected

Growing

Behavior Analytics

Google AnalyticsFree

User behavior and product analytics

Sponsored

Scripts & Styles

30 Resources

Scripts

Styles

Async

Defer

Top Script Sources

chaostreff-dortmund.de(20)

Sponsored

Last analyzed: 18 Feb 2026 at 06:03

Historical Analysis & Change Tracking