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leiden.nl

https://leiden.nl· First analyzed 05 May 2026· Updated 05 May 2026
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leiden.nl
Desktop screenshot of leiden.nl
Mobile screenshot of leiden.nl
Mobile

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Hosting Provider

True B.V

IP Address

87.233.198.3

Site Location

🇳🇱 Netherlandsvia tld

Server Location

🇳🇱 Amsterdam, The Netherlands

ASN

AS15703

Organization

True B.V

CDN

CDN

Nameservers

ns2.hostingcore.eu.ns3.hostingcore.domains.ns1.hostingcore.nl.

Performance

100

Core Web Vitals

Weight

First Contentful Paint
612 ms10%
Speed Index
796 ms10%
Largest Contentful Paint
—25%
Total Blocking Time
0.0 ms30%
Cumulative Layout Shift
0.00025%
75 KB
38 requests

Image Optimization

Lazy LoadWebPResponsive
0–49
50–89
90–100

Architecture Stack

Monolithic
⚙️ SSR
Infrastructure
Hosting
True B.V
CDN
CDN

Technology Stack

6 Technologies Detected

Fonts

2
Adobe Fonts (Typekit)Adobe Fonts

Analytics

2
Google Analytics
Google Analytics 4

CSS Frameworks

1
Tailwind CSS

Tag Managers

1
Google Tag Manager

SEO Analysis

D57/100
19
6
2
Meta Tags4/15
Content8/12
Headings8/8
Technical17/25
E-E-A-T0/7
Images3/7
Links5/5
URL5/5
Social0/5
Freshness0/4
Mobile4/4
Indexability3/3
L
leiden.nlleiden.nl

Landingpage | Visit Leiden

No description available for this page.

Title Length26 chars

Recommended: 50-60 chars (~150px / 580px)

Description Length0 chars

Recommended: 120-160 chars

Issues (2)

  • • Missing meta description — important for click-through rates in SERPs
  • • Most images missing alt text (4/5) — critical for accessibility and SEO

8 issues found

Upgrade to view details

Crawlability

Sitemap

Type: index

3 URLs

3 sub-sitemaps

robots.txt

16 rules

Sitemap reference found

Allows all crawlers

Local SEO

Local Search Readiness

7/100
Poor
2 14 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

F33/100
Bot Access
20/25
Machine Read.
7/25
Schema Data
0/25
Citation
6/25

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:2%
Words:83
Token eff.:Too Short
Sections/1K:10
Depth:1/5

Structured Data

No Schema

Citation Readiness

Opening Summary
Descriptive Headingsavg 3w
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...
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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
83/100
12
Passed
1
Critical
0
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
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
4/15
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.
67/100
A+
9 mg
CO₂e / view
75.4 KB
Page Weight
95%
Cleaner Than
New Visitor
11 mg
vs
Returning (cached)
5 mg
Annual (10K/mo)
1.1 kg
Emission Segments
Data Center
2 mg
Network
2 mg
Device
5 mg
Resource Breakdown
JavaScript
17.4 KB
Images
6.4 KB
CSS
28.3 KB
HTML
4.6 KB
Other
18.7 KB
Green Hosting Not Verified
True B.V
4 recommendations
  • •Carbon footprint recommendation preview...
Upgrade to view recommendations
B

Security Score

76%Good
Interactive

HTTPS

No WAF

75d

Certificate Details

Type

Domain Validated (DV)

Certificate Authority

Let's Encrypt

Key Algorithm

ECDSA (secp256r1) (256 bit)

Signature

ECDSA with SHA-384

TLS Version

TLSv1.3

HTTP Protocol

HTTP/2+H3

Valid From

21.04.2026

Valid Until

20.07.2026

Subject Alternative Names (1)

www.visitleiden.nl

SHA-256 Fingerprint

C6:C6:DB:DA:AE:B1:72:B1:09:DA:EA:1B:A4:EE:AB:B2:F5:13:D8:84...

Top Recommendations

Security recommendation preview

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Upgrade to view header details

HTTP Headers

Developer Console

accept-ranges
bytes
age
0
alt-svc
h3=":443"; ma=2592000
cache-control
🟡 0s(max-age=0, must-revalidate, private, s-maxage=3600)
content-encoding
📦 Gzip(gzip)
content-security-policy
default-src https: 'unsafe-inline' 'unsafe-eval' data: blob:...
Good Warning Issue

Email Infrastructure

Microsoft 365

Score

93

SPF
DKIM
DMARC

DMARC Policy

Quarantine (Moderate)

MX Records (1)

leiden-nl.mail.protection.outlook.com

Domain Information

leiden.nl

Domain Age
30y 2m

Created

22.02.1996

Last Updated

11.07.2025

Registrar

Registrar.eu

DNSSEC
Not Enabled

Privacy & Compliance

Cookie Consent Banner
Privacy Policy
Terms of Service

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=1.0

Typography & Readability

georgia + canada-type-gibson

WCAG Partial
76/100
Readability
/30
24/30

20px · LH 1.50

Hierarchy
/20
20/20

2.5x ratio · ✓ H1→H6

WCAG
/25
17/25

1:1 min contrast

Performance
/25
15/25

2 fonts · 1 req

Heading Font

georgia

Serif50px

Body Font

canada-type-gibson

Sans20px

Contrast Ratio

1:1

10 issues

Reading Comfort

Serif Headlines + Sans Body

left aligned
50px
h1
40px
h2

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

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

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

⚠️ Partial contrast: 10 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 2.5x larger than body text.

AAdobe FontsBuy on MyFontsFlesch 0

Color Palette

10 unique colors
21:1 AAA Light
#ffffff
Background· 44.699999999999996%
#000000
Primary· 38.300000000000004%
#25221e
Secondary· 2.8%
#6c584c
Secondary· 2.3%
#40617c
Secondary· 1.9%
#cdc5be
Secondary· 1.7%
#f6e8e1
Accent· 1.2000000000000002%

Business & Marketing Stack

3 Tools Detected

Advanced

Behavior Analytics

2
Google Tag ManagerFree
Google AnalyticsFree

User behavior and product analytics

Advertising

1
Pinterest AdsMid-Market

Ad platforms and retargeting pixels

2

Categories

3

Total Tools

0

Enterprise

1

Mid-Market

Assessment: Well-developed marketing technology stack

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Scripts & Styles

10 Resources

8
Scripts
2
Styles
6
Async
2
Defer

Top Script Sources

googletagmanager.com(3)s.pinimg.com(2)local(2)google-analytics.com(1)

Website Identity

leiden.nl

30 years old
Location detected: 🇳🇱 Netherlandsvia tld
Registrar.eu📧 Microsoft 365nl

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Last analyzed: 05 May 2026 at 23:26

Historical Analysis & Change Tracking