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gap-system.org

https://gap-system.org· First analyzed 11 May 2026· Updated 11 May 2026
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gap-system.org
Desktop screenshot of gap-system.org
Mobile screenshot of gap-system.org
Mobile

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Hosting Provider

Technische Universitaet Kaiserslautern

IP Address

131.246.120.130

Site Location

🇩🇪 Germanyvia ip

Server Location

🇩🇪 Kaiserslautern, Germany

ASN

AS199578

Organization

Technische Universitaet Kaiserslautern

Server

Nginx

Nameservers

ns1.rptu.de.ns2.rptu.de.

Performance

99

Core Web Vitals

Weight

First Contentful Paint
785 ms10%
Speed Index
1.0 s10%
Largest Contentful Paint
—25%
Total Blocking Time
0.0 ms30%
Cumulative Layout Shift
0.00025%
1.2 MB
14 requests
0–49
50–89
90–100

Architecture Stack

JAMstack
⚡ SSG
Frontend
Framework
Jekyllv4.4.1
Infrastructure
Hosting
Technische Universitaet Kaiserslautern

Technology Stack

2 Technologies Detected

CSS Frameworks

1
Tailwind CSS

Web Servers

1
Nginx

SEO Analysis

C60/100
16
7
1
Meta Tags7/15
Content9/12
Headings5/8
Technical16/21
E-E-A-T2/7
Images1/7
Links5/5
URL5/5
Social3/5
Freshness0/4
Mobile4/4
Indexability3/3
G
gap-system.orggap-system.org

Start | GAP

GAP system for computational discrete algebra, especially computational group theory

Title Length11 chars

Recommended: 50-60 chars (~68px / 580px)

Description Length84 chars

Recommended: 120-160 chars

Issues (1)

  • • Most images missing alt text (1/1) — critical for accessibility and SEO

8 issues found

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Local SEO

Local Search Readiness

10/100
Poor
3 13 1

This site doesn't appear to be a local business. Local SEO signals are optional for non-local websites.

Sponsored

AI & LLM Readiness

D49/100
Bot Access
20/25
Machine Read.
12/25
Schema Data
5/25
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
navheader/footer
Text ratio:10%
Words:483
Token eff.:Optimal
Sections/1K:12.4
Depth:2/5

Structured Data

1 JSON-LD
Organization×1.1WebSite

Citation Readiness

Opening Summary239w
Descriptive Headingsavg 3.2w
Canonical URL
Open Graph1/3
Twitter Card1/3
Language Tag
Publish Date
Author Info
Lists
Tables
TL;DR / Summary
About Page Link
Recommendations (9)
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
70/100
14
Passed
3
Critical
0
Warnings
Images & Alt Text
5/20
Checks if images have descriptive alt text for screen readers and visually impaired users.
Semantic Structure
17/20
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
11/15
Ensures all interactive elements are reachable and operable via keyboard (tab, enter, escape).
ARIA & Roles
7/15
Checks correct use of WAI-ARIA attributes (roles, states, properties) for assistive technologies.
1 recommendation
  • •Accessibility recommendation preview...
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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.
52/100
C
153 mg
CO₂e / view
1.2 MB
Page Weight
70%
Cleaner Than
New Visitor
175 mg
vs
Returning (cached)
88 mg
Annual (10K/mo)
18.4 kg
Emission Segments
Data Center
34 mg
Network
37 mg
Device
82 mg
Resource Breakdown
JavaScript
679.2 KB
Images
65.6 KB
CSS
223.9 KB
HTML
5.5 KB
Other
266.2 KB
Green Hosting Not Verified
Technische Universitaet Kaiserslautern
2 recommendations
  • •Carbon footprint recommendation preview...
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D

Security Score

56%Poor
Interactive

HTTPS

No WAF

88d

Certificate Details

Type

Domain Validated (DV)

Certificate Authority

Let's Encrypt

Key Algorithm

RSA (4096 bit)

Signature

SHA-256 with RSA

TLS Version

TLSv1.3

HTTP Protocol

HTTP/2

Valid From

10.05.2026

Valid Until

08.08.2026

Subject Alternative Names (1)

www.gap-system.org

SHA-256 Fingerprint

2E:6E:D3:DC:15:E1:DB:BC:2F:0E:87:82:30:A6:A9:12:C7:B7:A0:06...

Top Recommendations

Security recommendation preview

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HTTP Headers

Developer Console

accept-ranges
bytes
content-encoding
📦 Gzip(gzip)
content-length
5375
content-security-policy
upgrade-insecure-requests;
content-type
text/html
date
Mon, 11 May 2026 03:51:06 GMT
Good Warning Issue

Email Infrastructure

Custom Mail Server

Score

45

SPF
DKIM
DMARC

MX Records (2)

mailgate2.uni-kl.de
mailgate1.uni-kl.de

Domain Information

gap-system.org

Domain Age
25y 9m

Created

28.07.2000

Expires

28.07.2026

Last Updated

25.11.2025

Registrar

Key-Systems GmbH

DNSSEC
Not Enabled

Privacy & Compliance

Cookie Consent Banner
Privacy Policy
Terms of Service

GDPR Indicators

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
74/100
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
1 recommendation
  • •Mobile compatibility recommendation preview...
Upgrade to view recommendations

Typography & Readability

Ubuntu + -apple-system

WCAG AA
87/100
Readability
/30
29/30

16px · LH 1.60

Hierarchy
/20
15/20

2.25x ratio

WCAG
/25
22/25

6.86:1 min contrast

Performance
/25
21/25

System fonts

Heading Font

Ubuntu

Sans36px

Body Font

-apple-system

Sans16px

Contrast Ratio

6.86:1

WCAG AA (≥4.5:1)

Reading Comfort

~45 CPL

Optimal (45–75)
36px
h1
18px
h3
16px
p

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

✅ Optimal line spacing: 1.60 ratio (ideal range 1.4–1.6).

✅ Optimal line length: ~45 chars/line (ideal 45–75 CPL).

⚠️ Hard to read: Flesch score 47/100. Simplify sentences for wider reach.

✅ WCAG AA contrast: All text meets 4.5:1 ratio (min 6.9:1).

⚠️ Minor heading issue: 1 level skip(s) detected. Maintain sequential order for screen readers.

Buy on MyFontsFlesch 47

Color Palette

5 unique colors
2.04:1 Fail Light
#ffffff
Background· 86.89999999999999%
#bab4b7
Other· 4%
#59464b
Primary· 2.8%

Business & Marketing Stack

1 Tools Detected

Growing

Behavior Analytics

1
Google AnalyticsFree

User behavior and product analytics

1

Categories

1

Total Tools

0

Enterprise

0

Mid-Market

Assessment: Growing marketing technology adoption

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Scripts & Styles

8 Resources

4
Scripts
4
Styles
0
Async
2
Defer

Top Script Sources

local(4)

Website Identity

GAP

www.gap-system.org/
25 years old
Location detected: 🇩🇪 Germanyvia ip
Key-Systems GmbHen-US

Social Profiles

GitHub

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Last analyzed: 11 May 2026 at 03:51

Historical Analysis & Change Tracking