erfgoedleiden.nl

https://erfgoedleiden.nl· First analyzed 01 Jun 2026· Updated 01 Jun 2026

Export

erfgoedleiden.nl

Mobile

Sponsored

Hosting Provider

Vitec Memorix B.V

IP Address

195.93.224.192

Site Location

🇳🇱 Leiden, Netherlandsvia schema_nap

Server Location

🇳🇱 Heiloo, The Netherlands

ASN

AS49820

Organization

Vitec Memorix B.V

Server

Nginx

Nameservers

ns2.transip.eu.ns0.transip.net.ns1.transip.nl.

Performance

Core Web Vitals

Weight

First Contentful Paint

924 ms10%

Speed Index

1.2 s10%

Largest Contentful Paint

—25%

Total Blocking Time

0.0 ms30%

Cumulative Layout Shift

0.00025%

2.1 MB

50 requests

Image Optimization

Lazy Load

0–49

50–89

90–100

Architecture Stack

Monolithic

⚙️ SSR

Joomla!

Technology Stack

10 Technologies Detected

Analytics

Libraries

CSS Frameworks

Fonts

Web Servers

Customer Support

SEO Analysis

C64/100

Meta Tags7/15

Content11/12

Headings6/8

Technical17/25

E-E-A-T2/7

Images1/7

Links5/5

URL5/5

Social3/5

Freshness0/4

Mobile4/4

Indexability3/3

erfgoedleiden.nlerfgoedleiden.nl

Homepage

Erfgoed Leiden en Omstreken is hét cultuurhistorisch centrum voor gemeente Leiden en de regio. Hier werken archivisten, bouw- en architectuurhistorici, arche...

Description truncated.

Title Length8 chars

Recommended: 50-60 chars (~52px / 580px)

Description Length256 chars

Recommended: 120-160 chars

Issues (1)

• Most images missing alt text (8/8) — critical for accessibility and SEO

8 issues found

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Crawlability

Sitemap

robots.txt

15 rules

Local SEO

Local Search Readiness

31/100

Needs Work

9 12

Sponsored

AI & LLM Readiness

D49/100

Bot Access

20/25

Machine Read.

11/25

Schema Data

7/25

Citation

11/25

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

Text ratio:11%

Words:753

Token eff.:Optimal

Sections/1K:10.6

Structured Data

2 JSON-LD

Organization×1.1WebSiteSearchAction

sameAs entity links

Citation Readiness

Opening Summary14w

Descriptive Headingsavg 3.3w

Canonical URL

Open Graph3/3

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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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.

69/100

Passed

Critical

Warnings

Images & Alt Text

20/20

Checks if images have descriptive alt text for screen readers and visually impaired users.

Semantic Structure

14/20

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

1/15

Checks correct use of WAI-ARIA attributes (roles, states, properties) for assistive technologies.

2 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.

24/100

269 mg

CO₂e / view

2.1 MB

Page Weight

50%

Cleaner Than

New Visitor

307 mg

Returning (cached)

154 mg

Annual (10K/mo)

32.2 kg

Emission Segments

Data Center

60 mg

Network

65 mg

Device

144 mg

Resource Breakdown

JavaScript

373.2 KB

Images

635 B

CSS

1.7 MB

Fonts

722 B

HTML

10.4 KB

Other

514 B

Green Hosting Not Verified

Vitec Memorix B.V

5 recommendations

•Carbon footprint recommendation preview...

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Security Score

61%Fair

Interactive

HTTPS

No WAF

71d

Certificate Details

Type

Domain Validated (DV)

Certificate Authority

Let's Encrypt

Key Algorithm

RSA (2048 bit)

Signature

SHA-256 with RSA

TLS Version

TLSv1.3

HTTP Protocol

HTTP/2+H3

Valid From

13.05.2026

Valid Until

11.08.2026

Subject Alternative Names (13)

albums.erfgoedleiden.nlarchiefleiden.nlbeeldbanklisse.nlerfgoedleiden.nlleidenarchief.nlpilgrimarchives.nlregionaalarchiefleiden.nlwww.archiefleiden.nl+5 more

SHA-256 Fingerprint

3C:59:16:E4:20:41:16:06:7A:B6:27:81:87:59:B6:1E:30:A8:DE:DD...

Top Recommendations

Security recommendation preview

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HTTP Headers

Developer Console

alt-svc

h3=":443"; ma=60

cache-control

🔴 No Cache(no-store, no-cache, must-revalidate, post-check=0, pre-check...)

content-encoding

📦 Gzip(gzip)

content-type

text/html; charset=utf-8

date

Mon, 01 Jun 2026 14:57:25 GMT

expires

Wed, 17 Aug 2005 00:00:00 GMT

Good Warning Issue

Email Infrastructure

Microsoft 365

Score

SPF

DKIM

DMARC

DMARC Policy

Quarantine (Moderate)

MX Records (1)

erfgoedleiden-nl.mail.protection.outlook.com

Domain Information

erfgoedleiden.nl

Domain Age

16y 2m

Created

06.04.2010

Last Updated

05.02.2024

Registrar

team.blue nl B.V.

DNSSEC

Not Enabled

Privacy & Compliance

Cookie Consent Banner

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.

41/100

Not 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

user-scalable=no, width=device-width

4 recommendations

•Mobile compatibility recommendation preview...

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Typography & Readability

Lato

WCAG Partial

66/100

Readability

/30

22/30

16px · LH 1.60

Hierarchy

/20

13/20

3.25x ratio

WCAG

/25

16/25

1:1 min contrast

Performance

/25

15/25

1 font · 1 req

Heading Font

Lato

Sans52px

Body Font

Lato

Sans16px

Contrast Ratio

1:1

22 issues

Reading Comfort

Single Font Family

left aligned

52px

28px

16px

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

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

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

⚠️ Partial contrast: 22 elements below WCAG AA threshold (min 1.0:1).

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

✅ Strong hierarchy: Headlines are 3.2x larger than body text.

GGoogle FontsFlesch 0

Color Palette

11 unique colors

12.47:1 AAA Light

#ffffff

Background· 26.8%

#35342f

Other· 4.6%

#c46e30

Primary· 7.3%

#a69884

Secondary· 6.4%

#e2d7c7

Secondary· 5.3%

#775847

Secondary· 1.1%

Business & Marketing Stack

1 Tools Detected

Growing

Behavior Analytics

Google AnalyticsFree

User behavior and product analytics

Sponsored

Scripts & Styles

25 Resources

Scripts

Styles

Async

Defer

Top Script Sources

local(14)erfgoedleiden.nl(3)google-analytics.com(1)googletagmanager.com(1)ssl.mousestats.com(1)

Website Identity

Erfgoed Leiden en Omstreken

Organization

www.erfgoedleiden.nl/

16 years old

Boisotkade 2A, Leiden

2311 PZ, Leiden

Location detected: 🇳🇱 Netherlands, Leidenvia schema_nap

team.blue nl B.V.📧 Microsoft 365nl-nl

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Last analyzed: 01 Jun 2026 at 14:57

Historical Analysis & Change Tracking