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validator.nu

https://validator.nu· First analyzed 11 May 2026· Updated 11 May 2026
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validator.nu
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Hosting Provider

Gandi
gandi.net

IP Address

46.226.111.119

Site Location

🇱🇺 Luxembourgvia ip

Server Location

🇱🇺 Luxembourg, Luxembourg

ASN

AS29169

Server

Nginx

Nameservers

ns-130-c.gandi.net.ns-217-b.gandi.net.ns-2-a.gandi.net.

Performance

100

Core Web Vitals

Weight

First Contentful Paint
350 ms10%
Speed Index
455 ms10%
Largest Contentful Paint
—25%
Total Blocking Time
0.0 ms30%
Cumulative Layout Shift
0.00025%
15 KB
3 requests
0–49
50–89
90–100

Architecture Stack

Monolithic
⚙️ SSR
Infrastructure
Hosting
Gandi

Technology Stack

1 Technologies Detected

Web Servers

1
Nginxv1.18.0

SEO Analysis

D45/100
12
8
1
Meta Tags7/15
Content3/12
Headings8/8
Technical12/25
E-E-A-T0/7
Images0/7
Links3/5
URL5/5
Social0/5
Freshness0/4
Mobile4/4
Indexability3/3
V
validator.nuvalidator.nu

Validator.nu - Nu Html Checker

No description available for this page.

Title Length31 chars

Recommended: 50-60 chars (~186px / 580px)

Description Length0 chars

Recommended: 120-160 chars

Issues (1)

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

9 issues found

Upgrade to view details

Crawlability

Sitemap
robots.txt

2 rules

Local SEO

Local Search Readiness

3/100
Poor
1 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

F28/100
Bot Access
20/25
Machine Read.
4/25
Schema Data
0/25
Citation
4/25

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:9%
Words:52
Token eff.:Too Short
Sections/1K:10

Structured Data

No Schema

Citation Readiness

Opening Summary17w
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 (12)
AI readiness recommendation preview...
Upgrade to view recommendations

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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.
C
64/100
10
Passed
3
Critical
2
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
2/15
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.
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.
72/100
A+
2 mg
CO₂e / view
14.8 KB
Page Weight
95%
Cleaner Than
New Visitor
2 mg
vs
Returning (cached)
<0.001 g
Annual (10K/mo)
180 g
Emission Segments
Data Center
<0.001 g
Network
<0.001 g
Device
1 mg
Resource Breakdown
JavaScript
8.4 KB
Images
921 B
CSS
4.1 KB
HTML
1.3 KB
Green Hosting Verified
Gandi
Provider Match
3 recommendations
  • •Carbon footprint recommendation preview...
Upgrade to view recommendations
F

Security Score

36%Critical
Interactive

HTTPS

No WAF

77d

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

28.04.2026

Valid Until

27.07.2026

Subject Alternative Names (18)

about.validator.nubugzilla.validator.nudir2epub.comdir2epub.orghsivonen.comhsivonen.fihsivonen.iki.fihtml5.validator.nu+10 more

SHA-256 Fingerprint

80:63:69:6B:EA:72:C8:D6:B3:1F:B6:9D:EA:33:7B:FC:B9:16:59:2B...

Top Recommendations

Security recommendation preview

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Upgrade to view header details

HTTP Headers

Developer Console

accept-encoding
gzip
access-control-allow-headers
content-type
access-control-allow-origin
*
content-encoding
📦 Gzip(gzip)
content-type
text/html;charset=utf-8
date
Mon, 11 May 2026 03:48:10 GMT
Good Warning Issue

Email Infrastructure

Custom Mail Server

Score

20

SPF
DKIM
DMARC

MX Records (2)

spool.mail.gandi.net
fb.mail.gandi.net

Domain Information

validator.nu

DNSSEC
Not Enabled

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.
D
55/100
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...
Upgrade to view recommendations

Typography & Readability

Myriad Web + Arial

WCAG AA
76/100
Readability
/30
20/30

16px · LH --

Hierarchy
/20
14/20

1.6x ratio · ✓ H1→H6

WCAG
/25
22/25

4.67:1 min contrast

Performance
/25
20/25

System fonts

Heading Font

Myriad Web

Sans26px

Body Font

Arial

Sans16px

Contrast Ratio

4.67:1

WCAG AA (≥4.5:1)

Reading Comfort

~49 CPL

Optimal (45–75)
26px
h1
16px
h2
16px
p

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

✅ Optimal line length: ~49 chars/line (ideal 45–75 CPL).

❌ Very complex text: Flesch score 28/100. Consider shorter sentences and simpler words.

✅ WCAG AA contrast: All text meets 4.5:1 ratio (min 4.7:1).

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

✅ System fonts: Zero font loading delay — best possible LCP impact.

Buy on MyFontsFlesch 28

Color Palette

5 unique colors
Light
#ffffff
Background· 89.19999999999999%
#365d96
Primary· 5.3999999999999995%
#c7cbd1
Border· 2%
#697fa5
Secondary· 0.9%

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Scripts & Styles

2 Resources

1
Scripts
1
Styles
0
Async
0
Defer

Top Script Sources

script.js(1)

Website Identity

validator.nu

Location detected: 🇱🇺 Luxembourgvia ip
en

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Last analyzed: 11 May 2026 at 03:48

Historical Analysis & Change Tracking