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koelner-philharmonie.de

https://koelner-philharmonie.de· First analyzed 12 May 2026· Updated 12 May 2026
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koelner-philharmonie.de
Desktop screenshot of koelner-philharmonie.de
Mobile screenshot of koelner-philharmonie.de
Mobile

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Hosting Provider

Hetzner
hetzner.com

IP Address

94.130.188.32

Site Location

🇩🇪 Germanyvia phone

Server Location

🇩🇪 Nuremberg, Germany

ASN

AS24940

Organization

Hetzner Online GmbH

Server

Nginx

Nameservers

dns12.netcologne.de.dns11.netcologne.de.dns13.netcologne.de.dns14.netcologne.de.

Performance

100

Core Web Vitals

Weight

First Contentful Paint
425 ms10%
Speed Index
552 ms10%
Largest Contentful Paint
—25%
Total Blocking Time
0.0 ms30%
Cumulative Layout Shift
0.00025%
1.7 MB
50 requests

Image Optimization

Lazy LoadWebPResponsive
0–49
50–89
90–100

Architecture Stack

Hybrid
⚙️ SSR
Frontend
Framework
Nuxt.js
Infrastructure
Hosting
Hetzner

Technology Stack

7 Technologies Detected

Meta Frameworks

1
Nuxt.js

UI Components

1
Fancybox

Other

1
Lottie

CSS Frameworks

1
Tailwind CSS

Analytics

1
Google Analytics 4

Tag Managers

1
Google Tag Manager

Web Servers

1
Nginx

SEO Analysis

C66/100
21
6
2
Meta Tags9/15
Content3/12
Headings6/8
Technical23/25
E-E-A-T3/7
Images3/7
Links5/5
URL5/5
Social2/5
Freshness0/4
Mobile4/4
Indexability3/3
K
koelner-philharmonie.dekoelner-philharmonie.de

Kölner Philharmonie

Musical highlights from classical music, jazz, folk and pop in Cologne. Unique moments every day in one of the most modern concert halls in the world!

Title Length19 chars

Recommended: 50-60 chars (~111px / 580px)

Description Length150 chars

Recommended: 120-160 chars

Issues (2)

  • • Very thin content (2 words). Search engines need substantial content for ranking.
  • • Most images missing alt text (19/24) — critical for accessibility and SEO

8 issues found

Upgrade to view details

Crawlability

Sitemap

Type: index

12 URLs

12 sub-sitemaps

robots.txt

4 rules

Local SEO

Local Search Readiness

20/100
Needs Work
6 10 2

Sponsored

AI & LLM Readiness

F39/100
Bot Access
20/25
Machine Read.
7/25
Schema Data
3/25
Citation
9/25

AI Bot Access

14/14 accessible
AI Search
OAI-SearchBot
PerplexityBot
Claude-SearchBot
Gemini-Deep-Research
DuckAssistBot
Training
GPTBot
ClaudeBot
Google-Extended
Meta-ExternalAgent
Bytespiderinfo
Amazonbot
Applebot-Extended
CCBotinfo
Fetch
ChatGPT-User

Machine Readability

llms.txt
llms-full.txt
Semantic HTML
Heading Hierarchy
Text ratio:1%
Words:435
Token eff.:Optimal

Structured Data

Microdata
WebSitemicrodataBreadcrumbListmicrodataSearchActionmicrodata

Citation Readiness

Opening Summary
Descriptive Headings
Canonical URL
Open Graph3/3
Twitter Card0/3
Language Tag
Publish Date
Author Info
Lists
Tables
TL;DR / Summary
About Page Link
Recommendations (12)
AI readiness recommendation preview...
Upgrade to view recommendations

Sponsored

Accessibility

WCAG 2.1 Compliance

Evaluates how accessible your website is for users with disabilities, based on WCAG 2.1 guidelines. Checks images, forms, keyboard navigation, ARIA roles, and color contrast.
A
80/100
12
Passed
3
Critical
1
Warnings
Images & Alt Text
20/20
Checks if images have descriptive alt text for screen readers and visually impaired users.
Semantic Structure
11/20
Evaluates proper use of HTML5 semantic elements (header, nav, main, footer) and heading hierarchy.
Forms & Inputs
15/15
Verifies form fields have labels, error messages are clear, and inputs are properly associated.
Color & Contrast
15/15
Tests text-to-background color contrast ratios against WCAG AA/AAA minimum requirements.
Keyboard & Focus
15/15
Ensures all interactive elements are reachable and operable via keyboard (tab, enter, escape).
ARIA & Roles
4/15
Checks correct use of WAI-ARIA attributes (roles, states, properties) for assistive technologies.
2 recommendations
  • •Accessibility recommendation preview...
Upgrade to view recommendations

Carbon Footprint

SWDM v4 · Eco-Score

Carbon emissions estimated using the Sustainable Web Design Model v4 (SWDM v4). Factors in data center, network, and device energy across new and returning visitors. Grade thresholds based on HTTP Archive percentiles.
71/100
C
178 mg
CO₂e / view
1.7 MB
Page Weight
60%
Cleaner Than
New Visitor
203 mg
vs
Returning (cached)
102 mg
Annual (10K/mo)
21.3 kg
Emission Segments
Data Center
9 mg
Network
52 mg
Device
117 mg
Resource Breakdown
JavaScript
712.3 KB
Images
875.7 KB
CSS
85.5 KB
HTML
58.9 KB
Other
25.9 KB
Green Hosting Verified
Hetzner Online GmbH
GWF Verified
3 recommendations
  • •Carbon footprint recommendation preview...
Upgrade to view recommendations
F

Security Score

36%Critical
Interactive

HTTPS

No WAF

151d

Certificate Details

Type

Domain Validated (DV)

Certificate Authority

Sectigo Limited

Key Algorithm

RSA (2048 bit)

Signature

SHA-256 with RSA

TLS Version

TLSv1.3

HTTP Protocol

HTTP/2

Valid From

26.03.2026

Valid Until

10.10.2026

OCSP Stapling

Enabled

Subject Alternative Names (2)

www.koelner-philharmonie.dekoelner-philharmonie.de

SHA-256 Fingerprint

0F:95:AD:0F:2F:C0:1C:9E:98:01:BE:61:86:D9:EF:F9:34:CC:F1:DA...

Top Recommendations

Security recommendation preview

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HTTP Headers

Developer Console

cache-control
🟡 600s(max-age=600)
content-encoding
⚡ Brotli(br)
content-type
text/html; charset=utf-8
date
Tue, 12 May 2026 00:09:04 GMT
etag
"5de1b-oguLD1/M1Xckw81sQQNvPPEVyjw"
expires
Tue, 12 May 2026 00:19:04 GMT
Good Warning Issue

Email Infrastructure

Custom Mail Server

Score

90

SPF
DKIM
DMARC

DMARC Policy

None (Monitor Only)

MX Records (1)

b2bserver.de

Domain Information

koelner-philharmonie.de

Last Updated

11.12.2025

DNSSEC
Not Enabled

Privacy & Compliance

Cookie Consent Banner
Privacy Policy
Terms of Service

GDPR Indicators

Cookie consent banner detected
Privacy policy page linked

Mobile Compatibility

Viewport & Responsive Test

Tests how well your website works on mobile devices. Checks viewport configuration, responsive layout, touch targets, font readability, and simulates rendering across different screen sizes.
B
78/100
Mobile Friendly314 breakpoints
Viewport Meta
The viewport meta tag tells mobile browsers how to scale the page. Without it, mobile devices render at desktop width.
Responsive Design
Uses CSS media queries or flexible layouts to adapt content to different screen sizes automatically.
Touch Icons
Apple touch icons and favicons displayed when users add the site to their home screen on mobile devices.
Readable Font Size
Base font size should be at least 16px on mobile to ensure text is readable without zooming.
Relative Units
Using em, rem, %, or vw instead of fixed px values allows content to scale properly across screen sizes.
No H-Scroll Risk
No elements wider than the viewport that would cause horizontal scrolling on mobile devices.
Tap Targets OK
Interactive elements (buttons, links) are at least 48x48px with enough spacing to prevent accidental taps.
No Fixed Widths
No elements with fixed pixel widths that could overflow on smaller screens and break the layout.
Viewport
width=device-width, initial-scale=1.0, maximum-scale=5.0
2 recommendations
  • •Mobile compatibility recommendation preview...
Upgrade to view recommendations

Typography & Readability

Gustavo + Neutral

WCAG Partial
72/100
Readability
/30
23/30

16px · LH 1.20

Hierarchy
/20
16/20

4.5x ratio

WCAG
/25
13/25

1:1 min contrast

Performance
/25
20/25

2 fonts · 3 req

Heading Font

Gustavo

Sans72px

Body Font

Neutral

Sans16px

Contrast Ratio

1:1

8 issues

Reading Comfort

~42 CPL

Narrow lines
72px
h1
36px
h2
40px
h3
16px
p

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

⚠️ Tight line spacing (1.20). Increase to 1.4–1.6 for better readability.

⚠️ Hard to read: Flesch score 44/100. Simplify sentences for wider reach.

⚠️ Partial contrast: 8 elements below WCAG AA threshold (min 1.0:1).

⚠️ Minor heading issue: 0 level skip(s) detected. Maintain sequential order for screen readers.

✅ Strong hierarchy: Headlines are 4.5x larger than body text.

Buy on MyFontsFlesch 45

Color Palette

9 unique colors
8.51:1 AAA Dark
#4e4c4e
Other· 25.8%
#ffffff
Background· 22%
#995f11
Primary· 10%
#461d40
Secondary· 4.2%

Business & Marketing Stack

2 Tools Detected

Growing

Behavior Analytics

2
Google Tag ManagerFree
Google AnalyticsFree

User behavior and product analytics

1

Categories

2

Total Tools

0

Enterprise

0

Mid-Market

Assessment: Growing marketing technology adoption

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Scripts & Styles

20 Resources

20
Scripts
0
Styles
15
Async
14
Defer

Top Script Sources

koelner-philharmonie.de(17)load.sst.koelner-philharmonie.de(3)

Website Identity

koelner-philharmonie.de

+49221280280
Location detected: 🇩🇪 Germanyvia phone
en

Sponsored

Last analyzed: 12 May 2026 at 00:09

Historical Analysis & Change Tracking