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ddb.de

https://ddb.de· First analyzed 03 May 2026· Updated 03 May 2026
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ddb.de
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Mobile

Sponsored

Hosting Provider

FIZ Karlsruhe - Leibniz Institute Information Infrastructure

IP Address

141.66.192.62

Site Location

🇩🇪 Germanyvia tld

Server Location

🇩🇪 Eggenstein-Leopoldshafen, Germany

ASN

AS13040

Organization

FIZ Karlsruhe - Leibniz Institute Information Infrastructure

Nameservers

dns1.fiz-karlsruhe.de.dns2.fiz-karlsruhe.de.deneb.dfn.de.

Performance

100

Core Web Vitals

Weight

First Contentful Paint
637 ms10%
Speed Index
828 ms10%
Largest Contentful Paint
—25%
Total Blocking Time
0.0 ms30%
Cumulative Layout Shift
0.00025%
691 KB
152 requests

Image Optimization

Lazy LoadWebPResponsive
0–49
50–89
90–100

Architecture Stack

Monolithic
⚙️ SSR
Frontend
Styling
Bootstrap
CMS
Drupal
Infrastructure
Hosting
FIZ Karlsruhe - Leibniz Institute Information Infrastructure

Progressive Web App

Web ManifestApple Touch Icon

Technology Stack

4 Technologies Detected

CSS Frameworks

2
Tailwind CSS
Bootstrap

Other

1
D3.js

Analytics

1
Matomo

SEO Analysis

B71/100
21
7
0
Meta Tags15/15
Content12/12
Headings8/8
Technical18/25
E-E-A-T0/7
Images4/7
Links5/5
URL5/5
Social0/5
Freshness0/4
Mobile1/4
Indexability3/3
D
ddb.deddb.de

Deutsche Digitale Bibliothek - Kultur und Wissen online

Die Deutsche Digitale Bibliothek ist das zentrale Portal für Kultur und Wissen. Sie macht das kulturelle Erbe der Bundesrepublik über das Internet zugänglich.

Title Length55 chars

Recommended: 50-60 chars (~321px / 580px)

Description Length158 chars

Recommended: 120-160 chars

Issues (0)

    7 issues found

    Upgrade to view details

    Crawlability

    Sitemap

    Type: index

    1,867 URLs

    1867 sub-sitemaps

    robots.txt

    5 rules

    Sitemap reference found

    Local SEO

    Local Search Readiness

    6/100
    Poor
    2 13 2

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

    Sponsored

    AI & LLM Readiness

    D43/100
    Bot Access
    20/25
    Machine Read.
    11/25
    Schema Data
    0/25
    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:5%
    Words:1,190
    Token eff.:Optimal
    Sections/1K:54.6
    Depth:1/5

    Structured Data

    No Schema

    Citation Readiness

    Opening Summary54w
    Descriptive Headingsavg 4.4w
    Canonical URL
    Open Graph0/3
    Twitter Card0/3
    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.
    A
    83/100
    14
    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
    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
    9/15
    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.
    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.
    47/100
    B
    85 mg
    CO₂e / view
    690.8 KB
    Page Weight
    80%
    Cleaner Than
    New Visitor
    98 mg
    vs
    Returning (cached)
    49 mg
    Annual (10K/mo)
    10.2 kg
    Emission Segments
    Data Center
    19 mg
    Network
    21 mg
    Device
    46 mg
    Resource Breakdown
    JavaScript
    265.0 KB
    Images
    24.3 KB
    CSS
    381.7 KB
    HTML
    19.8 KB
    Green Hosting Not Verified
    FIZ Karlsruhe - Leibniz Institute Information Infrastructure
    5 recommendations
    • •Carbon footprint recommendation preview...
    Upgrade to view recommendations
    D

    Security Score

    55%Poor
    Critical / Transactional

    HTTPS

    No WAF

    200d

    Certificate Details

    Type

    Organization Validated (OV)

    Certificate Authority

    Hellenic Academic and Research Institutions CA

    Key Algorithm

    RSA (4096 bit)

    Signature

    SHA-256 with RSA

    TLS Version

    TLSv1.3

    HTTP Protocol

    HTTP/1.1

    Valid From

    19.11.2025

    Valid Until

    19.11.2026

    OCSP Stapling

    Enabled

    Subject Alternative Names (2)

    *.deutsche-digitale-bibliothek.dedeutsche-digitale-bibliothek.de

    SHA-256 Fingerprint

    CD:04:FF:77:84:70:7C:DA:90:A6:E2:6C:BB:14:1E:08:84:FB:5D:78...

    Top Recommendations

    Security recommendation preview

    Upgrade to view recommendations
    Upgrade to view header details

    HTTP Headers

    Developer Console

    connection
    Keep-Alive
    content-encoding
    📦 Gzip(gzip)
    content-language
    de-DE
    content-security-policy
    default-src 'none'; script-src 'self' 'unsafe-eval' 'unsafe-...
    content-type
    text/html;charset=UTF-8
    date
    Sun, 03 May 2026 03:49:34 GMT
    Good Warning Issue

    Email Infrastructure

    Custom Mail Server

    Score

    50

    SPF
    DKIM
    DMARC

    MX Records (2)

    mx20.system-hoster.com
    mx21.system-hoster.com

    Domain Information

    ddb.de

    Last Updated

    11.06.2018

    DNSSEC
    Not Enabled

    Privacy & Compliance

    Cookiebot

    Cookie Consent Banner
    Cookiebot
    Privacy Policy
    Terms of Service

    GDPR Indicators

    Cookie consent banner detected
    CMP: Cookiebot
    Privacy policy page linked
    Data Protection Officer mentioned

    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
    73/100
    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

    Inter

    WCAG Partial
    74/100
    Readability
    /30
    25/30

    20px · LH 1.40

    Hierarchy
    /20
    17/20

    2x ratio · ✓ H1→H6

    WCAG
    /25
    12/25

    1:1 min contrast

    Performance
    /25
    20/25

    1 font · 3 req

    Heading Font

    Inter

    Sans40px

    Body Font

    Inter

    Sans20px

    Contrast Ratio

    1:1

    7 issues

    Reading Comfort

    ~37 CPL

    Narrow lines
    40px
    h1
    40px
    h2
    24px
    h3
    20px
    p

    ✅ Excellent readability: 20px body text is ideal for all devices.

    ✅ Optimal line spacing: 1.40 ratio (ideal range 1.4–1.6).

    ❌ Very complex text: Flesch score 14/100. Consider shorter sentences and simpler words.

    ⚠️ Partial contrast: 7 elements below WCAG AA threshold (min 1.0:1).

    ✅ Perfect heading hierarchy: Sequential h1→h2→h3 with single H1 — ideal for SEO & accessibility.

    ✅ Strong hierarchy: Headlines are 2.0x larger than body text.

    Buy on MyFontsFlesch 14

    Color Palette

    5 unique colors
    Light
    #c5c4c2
    Other· 25.9%
    #ac173a
    Primary· 27.7%
    #8d133a
    Accent· 21.499999999999996%
    #a28f8c
    Secondary· 7.3%

    Business & Marketing Stack

    2 Tools Detected

    Growing

    Behavior Analytics

    2
    Matomo (Piwik)Mid-Market
    Google AnalyticsFree

    User behavior and product analytics

    1

    Categories

    2

    Total Tools

    0

    Enterprise

    1

    Mid-Market

    Assessment: Growing marketing technology adoption

    Sponsored

    Scripts & Styles

    11 Resources

    9
    Scripts
    2
    Styles
    2
    Async
    1
    Defer

    Top Script Sources

    local(7)cdn.matomo.cloud(1)deutschedigitalebibliothek.matomo.cloud(1)

    Website Identity

    ddb.de

    Location detected: 🇩🇪 Germanyvia tld
    de

    Sponsored

    Last analyzed: 03 May 2026 at 03:49

    Historical Analysis & Change Tracking