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leiden.edu

https://leiden.edu· First analyzed 30 Apr 2026· Updated 30 Apr 2026
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leiden.edu
Desktop screenshot of leiden.edu
Mobile screenshot of leiden.edu
Mobile

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Hosting Provider

Universiteit Leiden

IP Address

132.229.92.35

Site Location

🇳🇱 Netherlandsvia ip

Server Location

🇳🇱 Leiden, Netherlands

ASN

AS1103

Organization

Universiteit Leiden

Nameservers

ns3.surfnet.nl.ns2.surfnet.nl.ns1.surfnet.nl.

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%
7.3 MB
36 requests

Image Optimization

Responsive
0–49
50–89
90–100

Architecture Stack

Monolithic
⚙️ SSR
Infrastructure
Hosting
Universiteit Leiden

Technology Stack

5 Technologies Detected

Analytics

2
Google Analytics
Google Analytics 4

Libraries

1
jQuery

CSS Frameworks

1
Tailwind CSS

Tag Managers

1
Google Tag Manager

SEO Analysis

C68/100
21
5
1
Meta Tags7/15
Content9/12
Headings8/8
Technical18/25
E-E-A-T0/7
Images2/7
Links5/5
URL5/5
Social5/5
Freshness2/4
Mobile4/4
Indexability3/3
L
leiden.eduleiden.edu

Home - Leiden University

Leiden University, The Netherlands, was founded in 1575 and is one of Europe’s leading international research universities. It has seven faculties in the art...

Description truncated.
Title Length24 chars

Recommended: 50-60 chars (~145px / 580px)

Description Length301 chars

Recommended: 120-160 chars

Issues (1)

  • • Most images missing alt text (6/7) — critical for accessibility and SEO

6 issues found

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Crawlability

Sitemap

Type: index

45 URLs

45 sub-sitemaps

robots.txt

7 rules

Sitemap reference found

Local SEO

Local Search Readiness

8/100
Poor
3 13 2

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

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AI & LLM Readiness

D48/100
Bot Access
20/25
Machine Read.
13/25
Schema Data
0/25
Citation
15/25

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:8%
Words:379
Token eff.:Optimal
Sections/1K:18.5
Depth:2/5

Structured Data

No Schema

Citation Readiness

Opening Summary22w
Descriptive Headingsavg 2w
Canonical URL
Open Graph3/3
Twitter Card3/3
Language Tag
Publish Date
Author Info
Lists
Tables
TL;DR / Summary
About Page Link
Recommendations (7)
AI readiness recommendation preview...
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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
85/100
12
Passed
2
Critical
0
Warnings
Images & Alt Text
20/20
Checks if images have descriptive alt text for screen readers and visually impaired users.
Semantic Structure
18/20
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
13/15
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.

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.
16/100
F
919 mg
CO₂e / view
7.3 MB
Page Weight
5%
Cleaner Than
New Visitor
1.05 g
vs
Returning (cached)
525 mg
Annual (10K/mo)
110.3 kg
Emission Segments
Data Center
205 mg
Network
221 mg
Device
493 mg
Resource Breakdown
JavaScript
44.3 KB
Images
6.8 MB
CSS
435.1 KB
HTML
6.4 KB
Other
1.2 KB
Green Hosting Not Verified
Universiteit Leiden
7 recommendations
  • •Carbon footprint recommendation preview...
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A

Security Score

81%Very Good
Interactive

HTTPS

No WAF

110d

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

18.08.2025

Valid Until

18.08.2026

OCSP Stapling

Enabled

Subject Alternative Names (20)

cms.universiteitleiden.nlwww.bibliotheek.universiteitleiden.nlorganisatiegids.universiteitleiden.nlwww.luf.nlwww.medewerkers.universiteitleiden.nlbibliotheek.universiteitleiden.nlmedewerkers.universiteitleiden.nlluf.nl+12 more

SHA-256 Fingerprint

85:90:A2:14:6C:CF:D2:E8:D5:E3:05:04:E0:02:84:21:91:2A:51:35...

Top Recommendations

Security recommendation preview

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Upgrade to view header details

HTTP Headers

Developer Console

access-control-allow-methods
GET
access-control-allow-origin
*
access-control-max-age
3600
content-encoding
📦 Gzip(gzip)
content-security-policy
frame-ancestors 'self' https://leidenuniv.libwizard.com http...
content-type
text/html;charset=UTF-8
Good Warning Issue

Email Infrastructure

Custom Mail Server

Score

93

SPF
DKIM
DMARC

DMARC Policy

Quarantine (Moderate)

MX Records (1)

leiden-edu.f-v1.mx.microsoft

Domain Information

leiden.edu

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

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
67/100
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
3 recommendations
  • •Mobile compatibility recommendation preview...
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Typography & Readability

vestula + georgia

WCAG Partial
68/100
Readability
/30
20/30

16px · LH 1.38

Hierarchy
/20
17/20

2x ratio

WCAG
/25
16/25

3.37:1 min contrast

Performance
/25
15/25

2 fonts · 3 req

Heading Font

vestula

Sans32px

Body Font

georgia

Serif16px

Contrast Ratio

3.37:1

11 issues

Reading Comfort

Sans Headlines + Serif Body

left aligned
32px
h1
27px
h2
16px
p

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

⚠️ Tight line spacing (1.38). Increase to 1.4–1.6 for better readability.

❌ Very complex text: Flesch score 0/100. Consider shorter sentences and simpler words.

⚠️ Partial contrast: 11 elements below WCAG AA threshold (min 3.4:1).

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

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

Buy on MyFontsFlesch 0

Color Palette

7 unique colors
Light
#ffffff
Background· 18.2%
#68769b
Secondary· 62.7%
#010e56
Primary· 4.8%
#7c86a1
Secondary· 1.6%
#3e4c7b
Primary· 0.9%

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

17 Resources

16
Scripts
1
Styles
16
Async
1
Defer

Top Script Sources

local(13)googletagmanager.com(3)

Website Identity

leiden.edu

Location detected: 🇳🇱 Netherlandsvia ip
en

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Last analyzed: 30 Apr 2026 at 13:15

Historical Analysis & Change Tracking