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stulz.com

https://stulz.com· First analyzed 22 May 2026· Updated 22 May 2026
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stulz.com
Desktop screenshot of stulz.com
Mobile screenshot of stulz.com
Mobile

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Hosting Provider

maxcluster GmbH

IP Address

194.6.210.31

Site Location

🇩🇪 Germanyvia ip

Server Location

🇩🇪 Paderborn, Germany

ASN

AS47447

Organization

maxcluster GmbH

Server

Nginx

Nameservers

ns4.p1.omc.info.ns1.p1.omc.net.ns3.p1.omcnet.de.

Performance

96

Core Web Vitals

Weight

First Contentful Paint
1.1 s10%
Speed Index
1.4 s10%
Largest Contentful Paint
—25%
Total Blocking Time
0.0 ms30%
Cumulative Layout Shift
0.00025%
11.6 MB
34 requests

Image Optimization

Responsive
0–49
50–89
90–100

Architecture Stack

Monolithic
⚙️ SSR
TYPO3

Technology Stack

4 Technologies Detected

CSS Frameworks

1
Tailwind CSS

Analytics

1
Google Analytics

Tag Managers

1
Google Tag Manager

Web Servers

1
Nginxv1.28.3

SEO Analysis

B75/100
21
7
1
Meta Tags12/15
Content12/12
Headings6/8
Technical24/25
E-E-A-T2/7
Images1/7
Links5/5
URL5/5
Social4/5
Freshness0/4
Mobile1/4
Indexability3/3
S
stulz.comstulz.com

Stulz: Your Global Cooling Expert.

Over 50 years as a leading pioneer in cooling solutions for reliable applications and data centers. Energy-efficient cooling for mission-critical applications.

Title Length34 chars

Recommended: 50-60 chars (~198px / 580px)

Description Length159 chars

Recommended: 120-160 chars

Issues (1)

  • • Most images missing alt text (6/9) — critical for accessibility and SEO

8 issues found

Upgrade to view details

Crawlability

Sitemap

Type: index

3 URLs

3 sub-sitemaps

robots.txt

28 rules

Sitemap reference found

Local SEO

Local Search Readiness

24/100
Needs Work
7 12

Sponsored

AI & LLM Readiness

D46/100
Bot Access
20/25
Machine Read.
11/25
Schema Data
3/25
Citation
12/25

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
nav
Text ratio:6%
Words:1,374
Token eff.:Optimal
Sections/1K:2.9
Depth:1/5

Structured Data

1 JSON-LD
Organization×1.1
sameAs entity links

Citation Readiness

Opening Summary212w
Descriptive Headingsavg 2.1w
Canonical URL
Open Graph3/3
Twitter Card1/3
Language Tag
Publish Date
Author Info
Lists
Tables
TL;DR / Summary
About Page Link
Recommendations (10)
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.
B
73/100
10
Passed
3
Critical
2
Warnings
Images & Alt Text
20/20
Checks if images have descriptive alt text for screen readers and visually impaired users.
Semantic Structure
15/20
Evaluates proper use of HTML5 semantic elements (header, nav, main, footer) and heading hierarchy.
Forms & Inputs
10/15
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
9/15
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.
3 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.
48/100
F
1.20 g
CO₂e / view
11.6 MB
Page Weight
5%
Cleaner Than
New Visitor
1.37 g
vs
Returning (cached)
685 mg
Annual (10K/mo)
143.8 kg
Emission Segments
Data Center
59 mg
Network
352 mg
Device
787 mg
Resource Breakdown
JavaScript
315.0 KB
Images
890.5 KB
CSS
142.0 KB
HTML
13.5 KB
Other
10.3 MB
Green Hosting Verified
23M GmbH
GWF Verified
5 recommendations
  • •Carbon footprint recommendation preview...
Upgrade to view recommendations
C

Security Score

66%Fair
Interactive

HTTPS

No WAF

228d

Certificate Details

Type

Domain Validated (DV)

Certificate Authority

Sectigo Limited

Key Algorithm

RSA (4096 bit)

Signature

SHA-256 with RSA

TLS Version

TLSv1.3

HTTP Protocol

HTTP/2

Valid From

05.12.2025

Valid Until

05.01.2027

OCSP Stapling

Enabled

Subject Alternative Names (2)

*.stulz.comstulz.com

SHA-256 Fingerprint

63:AC:A4:FA:A3:2E:8D:11:B5:76:C3:BF:65:83:31:0E:B5:60:4A:4E...

Top Recommendations

Security recommendation preview

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Upgrade to view header details

HTTP Headers

Developer Console

cache-control
🟡 10 Hours(max-age=36685)
content-encoding
⚡ Brotli(br)
content-language
en
content-type
text/html; charset=utf-8
date
Fri, 22 May 2026 11:48:35 GMT
etag
W/"b71b459ff77dda0449c8c789d280dc9c"
Good Warning Issue

Email Infrastructure

Custom Mail Server

Score

70

SPF
DKIM
DMARC

DMARC Policy

None (Monitor Only)

MX Records (2)

mail1.stulz.de
mail2.stulz.de

Domain Information

stulz.com

Domain Age
29y 10m

Created

01.08.1996

Expires

31.07.2026

Last Updated

26.11.2025

Registrar

Key-Systems GmbH

DNSSEC
Not Enabled

Privacy & Compliance

Usercentrics

Cookie Consent Banner
Usercentrics
Privacy Policy
Terms of Service

GDPR Indicators

Cookie consent banner detected
CMP: Usercentrics
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.
C
68/100
Mobile Friendly1 breakpoint
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
2 recommendations
  • •Mobile compatibility recommendation preview...
Upgrade to view recommendations

Typography & Readability

Theinhardt

WCAG Partial
74/100
Readability
/30
24/30

16px · LH 1.50

Hierarchy
/20
18/20

3.12x ratio

WCAG
/25
17/25

1:1 min contrast

Performance
/25
15/25

1 font · 2 req

Heading Font

Theinhardt

Sans50px

Body Font

Theinhardt

Sans16px

Contrast Ratio

1:1

4 issues

Reading Comfort

~34 CPL

Narrow lines
50px
h1
30px
h2
20px
h3
24px
h4
16px
p

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

✅ Optimal line spacing: 1.50 ratio (ideal range 1.4–1.6).

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

⚠️ Partial contrast: 4 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 3.1x larger than body text.

Buy on MyFontsFlesch 44

Color Palette

9 unique colors
3.6:1 AA Large Light
#ffffff
Background· 33%
#81888b
Other· 6.1%
#476dfe
Primary· 0%
#dbe8e9
Secondary· 26.700000000000003%
#9cc6cd
Secondary· 6.2%
#b3d0d5
Secondary· 6.1%
#7eacb5
Secondary· 6.1%
#88484c
Secondary· 4.8%

Business & Marketing Stack

2 Tools Detected

Growing

Behavior Analytics

2
Google AnalyticsFree
Google Tag ManagerFree

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

10 Resources

7
Scripts
3
Styles
3
Async
0
Defer

Top Script Sources

app.usercentrics.eu(2)local(2)privacy-proxy.usercentrics.eu(1)googletagmanager.com(1)app.varify.io(1)

Website Identity

Stulz

Stulz

Organization
www.stulz.com/en/
29 years old
Location detected: 🇩🇪 Germanyvia ip
Key-Systems GmbHen

Sponsored

Last analyzed: 22 May 2026 at 11:48

Historical Analysis & Change Tracking