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onb.ac.at

https://onb.ac.at· First analyzed 22 Apr 2026· Updated 22 Apr 2026
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onb.ac.at
Desktop screenshot of onb.ac.at
Mobile screenshot of onb.ac.at
Mobile

Sponsored

Hosting Provider

ACOnet

IP Address

193.170.112.209

Site Location

🇦🇹 Austriavia tld

Server Location

🇦🇹 Vienna, Austria

ASN

AS1853

Server

Apache

Nameservers

ns5.univie.ac.at.ns1.onb.ac.at.ns2.onb.ac.at.

Performance

100

Core Web Vitals

Weight

First Contentful Paint
484 ms10%
Speed Index
629 ms10%
Largest Contentful Paint
—25%
Total Blocking Time
0.0 ms30%
Cumulative Layout Shift
0.00025%
13.8 MB
37 requests

Image Optimization

Lazy Load
0–49
50–89
90–100

Architecture Stack

Monolithic
⚙️ SSR
TYPO3

Technology Stack

3 Technologies Detected

CSS Frameworks

1
Tailwind CSS

Analytics

1
Matomo

Web Servers

1
Apache

SEO Analysis

B76/100
22
6
0
Meta Tags12/15
Content10/12
Headings8/8
Technical20/25
E-E-A-T0/7
Images5/7
Links5/5
URL5/5
Social4/5
Freshness0/4
Mobile4/4
Indexability3/3
O
onb.ac.atonb.ac.at

Österreichische Nationalbibliothek - Startseite

Herzlich willkommen in der Österreichischen Nationalbibliothek – der größten Bibliothek und zentralen Gedächtnisinstitution des Landes. Nützen Sie den Bibli...

Description truncated.
Title Length47 chars

Recommended: 50-60 chars (~273px / 580px)

Description Length356 chars

Recommended: 120-160 chars

Issues (0)

    6 issues found

    Upgrade to view details

    Crawlability

    Sitemap

    Type: index

    7 URLs

    7 sub-sitemaps

    robots.txt

    4 rules

    Sitemap reference found

    Allows all crawlers

    Local SEO

    Local Search Readiness

    10/100
    Poor
    3 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.
    9/25
    Schema Data
    0/25
    Citation
    14/25

    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:4%
    Words:5,582
    Token eff.:Acceptable
    Sections/1K:5
    Depth:1/5

    Structured Data

    No Schema

    Citation Readiness

    Opening Summary17w
    Descriptive Headingsavg 6.2w
    Canonical URL
    Open Graph2/3
    Twitter Card2/3
    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
    79/100
    13
    Passed
    1
    Critical
    3
    Warnings
    Images & Alt Text
    20/20
    Checks if images have descriptive alt text for screen readers and visually impaired users.
    Semantic Structure
    20/20
    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
    5/15
    Checks correct use of WAI-ARIA attributes (roles, states, properties) for assistive technologies.
    3 recommendations
    • •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.
    27/100
    F
    1.75 g
    CO₂e / view
    13.8 MB
    Page Weight
    5%
    Cleaner Than
    New Visitor
    1.99 g
    vs
    Returning (cached)
    997 mg
    Annual (10K/mo)
    209.4 kg
    Emission Segments
    Data Center
    390 mg
    Network
    419 mg
    Device
    937 mg
    Resource Breakdown
    JavaScript
    168.6 KB
    Images
    13.3 MB
    CSS
    227.1 KB
    HTML
    48.7 KB
    Green Hosting Not Verified
    ACOnet
    6 recommendations
    • •Carbon footprint recommendation preview...
    Upgrade to view recommendations
    D

    Security Score

    46%Poor
    Interactive

    HTTPS

    No WAF

    320d

    Certificate Details

    Type

    Domain Validated (DV)

    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

    09.03.2026

    Valid Until

    09.03.2027

    OCSP Stapling

    Enabled

    Subject Alternative Names (14)

    onb.ac.atonb.atwebmail.onb.ac.atoenb.ac.atnetguides.onb.ac.atwww.oenb.ac.atjobs.onb.ac.atnationalbibliothek.at+6 more

    SHA-256 Fingerprint

    86:59:57:5D:61:03:E6:56:91:46:E7:95:33:80:EB:17:66:41:BD:D4...

    Top Recommendations

    Security recommendation preview

    Upgrade to view recommendations
    Upgrade to view header details

    HTTP Headers

    Developer Console

    cache-control
    🔴 No Cache(private, no-store, max-age=0)
    connection
    Keep-Alive
    content-encoding
    📦 Gzip(gzip)
    content-language
    de
    content-length
    49585
    content-type
    text/html; charset=utf-8
    Good Warning Issue

    Email Infrastructure

    Microsoft 365

    Score

    95

    SPF
    DKIM
    DMARC

    DMARC Policy

    None (Monitor Only)

    MX Records (1)

    onb-ac-at.mail.protection.outlook.com

    Domain Information

    onb.ac.at

    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.
    C
    64/100
    Mobile Friendly
    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
    2 recommendations
    • •Mobile compatibility recommendation preview...
    Upgrade to view recommendations

    Typography & Readability

    Inter

    WCAG Partial
    73/100
    Readability
    /30
    23/30

    16px · LH 1.44

    Hierarchy
    /20
    20/20

    3.14x ratio · ✓ H1→H6

    WCAG
    /25
    19/25

    4.02:1 min contrast

    Performance
    /25
    11/25

    2 fonts · 7 req

    Heading Font

    Inter

    Sans50px

    Body Font

    Inter

    Sans16px

    Contrast Ratio

    4.02:1

    Below AA

    Reading Comfort

    ~39 CPL

    Narrow lines
    50px
    h1
    35px
    h2
    50px
    h3
    16px
    p
    Minor Second
    Scale

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

    ✅ Optimal line spacing: 1.44 ratio (ideal range 1.4–1.6).

    ❌ Very complex text: Flesch score 21/100. Consider shorter sentences and simpler words.

    ⚠️ Partial contrast: 0 elements below WCAG AA threshold (min 4.0:1).

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

    ✅ Strong hierarchy: Headlines are 3.1x larger than body text.

    Buy on MyFontsFlesch 21

    Color Palette

    7 unique colors
    18.67:1 AAA Light
    #ffffff
    Background· 52.3%
    #141212
    Text· 5.8%

    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

    Sponsored

    Scripts & Styles

    4 Resources

    3
    Scripts
    1
    Styles
    1
    Async
    0
    Defer

    Top Script Sources

    local(2)eu.libraryh3lp.com(1)

    Website Identity

    onb.ac.at

    Location detected: 🇦🇹 Austriavia tld
    📧 Microsoft 365de-AT

    Sponsored

    Last analyzed: 22 Apr 2026 at 17:10

    Historical Analysis & Change Tracking