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4tu.nl

https://4tu.nl· First analyzed 18 May 2026· Updated 18 May 2026
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4tu.nl
Desktop screenshot of 4tu.nl
Mobile screenshot of 4tu.nl
Mobile

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Hosting Provider

DigitalOcean
digitalocean.com

IP Address

188.166.69.72

Site Location

🇳🇱 Netherlandsvia tld

Server Location

🇳🇱 Amsterdam, Netherlands

ASN

AS14061

Organization

Digital Ocean

Server

Nginx

Nameservers

ns-cloud-c2.googledomains.com.ns-cloud-c4.googledomains.com.ns-cloud-c3.googledomains.com.ns-cloud-c1.googledomains.com.

Performance

99

Core Web Vitals

Weight

First Contentful Paint
792 ms10%
Speed Index
1.0 s10%
Largest Contentful Paint
—25%
Total Blocking Time
0.0 ms30%
Cumulative Layout Shift
0.00025%
2.4 MB
37 requests
0–49
50–89
90–100

Architecture Stack

Monolithic
⚙️ SSR
Infrastructure
Hosting
DigitalOcean

Technology Stack

6 Technologies Detected

Analytics

2
Google Analytics
Google Analytics 4

CSS Frameworks

1
Tailwind CSS

Icon Libraries

1
Font Awesome

Tag Managers

1
Google Tag Manager

Web Servers

1
Nginx

SEO Analysis

C64/100
17
7
1
Meta Tags4/15
Content11/12
Headings6/8
Technical20/25
E-E-A-T0/7
Images4/7
Links5/5
URL5/5
Social2/5
Freshness0/4
Mobile4/4
Indexability3/3
4
4tu.nl4tu.nl

Home

No description available for this page.

Title Length4 chars

Recommended: 50-60 chars (~27px / 580px)

Description Length0 chars

Recommended: 120-160 chars

Issues (1)

  • • Missing meta description — important for click-through rates in SERPs

8 issues found

Upgrade to view details

Crawlability

Sitemap
robots.txt

4 rules

Local SEO

Local Search Readiness

16/100
Poor
5 10 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

D43/100
Bot Access
20/25
Machine Read.
12/25
Schema Data
1/25
Citation
10/25

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
data-nosnippet

Machine Readability

llms.txt
llms-full.txt
Semantic HTML
Heading Hierarchy
nav
Text ratio:14%
Words:896
Token eff.:Optimal
Sections/1K:1.1
Depth:1/5

Structured Data

1 JSON-LD
BreadcrumbList

Citation Readiness

Opening Summary111w
Descriptive Headingsavg 1w
Canonical URL
Open Graph2/3
Twitter Card0/3
Language Tag
Publish Date
Author Info
Lists
Tables
TL;DR / Summary
About Page Link
Recommendations (9)
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.
B
73/100
9
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
13/20
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
6/15
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.
49/100
D
243 mg
CO₂e / view
2.4 MB
Page Weight
30%
Cleaner Than
New Visitor
278 mg
vs
Returning (cached)
139 mg
Annual (10K/mo)
29.2 kg
Emission Segments
Data Center
12 mg
Network
72 mg
Device
160 mg
Resource Breakdown
JavaScript
96.7 KB
Images
36.4 KB
CSS
2.2 MB
HTML
9.7 KB
Green Hosting Verified
DigitalOcean
Provider Match
4 recommendations
  • •Carbon footprint recommendation preview...
Upgrade to view recommendations
A

Security Score

81%Very Good
Interactive

HTTPS

No WAF

63d

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

Valid From

22.04.2026

Valid Until

21.07.2026

Subject Alternative Names (4)

3tu.nl4tu.nlwww.3tu.nlwww.4tu.nl

SHA-256 Fingerprint

31:20:D2:36:82:8C:D1:3F:B7:15:64:39:C6:1C:79:56:9E:D0:9B:A9...

Top Recommendations

Security recommendation preview

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HTTP Headers

Developer Console

accept-ranges
bytes
content-encoding
📦 Gzip(gzip)
content-length
9667
content-security-policy
script-src 'self' https://www.google.com https://www.gstatic...
content-type
text/html; charset=UTF-8
date
Mon, 18 May 2026 15:45:00 GMT
Good Warning Issue

Email Infrastructure

Google Workspace

Score

45

SPF
DKIM
DMARC

MX Records (1)

smtp.google.com

Domain Information

4tu.nl

Domain Age
10y 7m

Created

07.10.2015

Last Updated

11.07.2025

Registrar

Registrar.eu

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 Friendly6 breakpoints
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...
Upgrade to view recommendations

Typography & Readability

Officina + Lato

WCAG Partial
74/100
Readability
/30
22/30

16px · LH 1.63

Hierarchy
/20
18/20

2.75x ratio

WCAG
/25
18/25

3.42:1 min contrast

Performance
/25
16/25

2 fonts · 8 req

Heading Font

Officina

Sans44px

Body Font

Lato

Sans16px

Contrast Ratio

3.42:1

1 issue

Reading Comfort

~39 CPL

Narrow lines
44px
h1
30px
h2
16px
p

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

⚠️ Hard to read: Flesch score 42/100. Simplify sentences for wider reach.

⚠️ Partial contrast: 1 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 2.8x larger than body text.

⚠️ Fluid type without rem: clamp() detected but missing rem units. May fail WCAG 1.4.4 zoom test.

Buy on MyFontsFluid TypeFlesch 42

Color Palette

9 unique colors
Light
#ffffff
Primary· 35.4%
#025167
Accent· 12.7%
#022028
Accent· 11.9%
#053741
Accent· 11.6%
#006289
Accent· 11.100000000000001%
#01789c
Accent· 7.5%
#aeccc6
Secondary· 4.8%
#3a493f
Secondary· 2.7%

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

2 Resources

1
Scripts
1
Styles
1
Async
0
Defer

Top Script Sources

local(1)

Website Identity

4tu.nl

projectleider@4tu.nl
10 years old
Location detected: 🇳🇱 Netherlandsvia tld
Registrar.eu📧 Google Workspacenl

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Last analyzed: 18 May 2026 at 15:45

Historical Analysis & Change Tracking