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web4u.cz

https://web4u.cz· First analyzed 03 May 2026· Updated 03 May 2026
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web4u.cz
Desktop screenshot of web4u.cz
Mobile screenshot of web4u.cz
Mobile

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Hosting Provider

Web4U s.r.o

IP Address

81.91.86.19

Site Location

🇨🇿 Czech Republicvia tld

Server Location

🇨🇿 Prague, Czechia

ASN

AS39790

Organization

Web4U s.r.o

Server

OpenResty

Nameservers

ns.web4u.cz.ns2.web4u.cz.

Performance

100

Core Web Vitals

Weight

First Contentful Paint
586 ms10%
Speed Index
762 ms10%
Largest Contentful Paint
—25%
Total Blocking Time
0.0 ms30%
Cumulative Layout Shift
0.00025%
588 KB
85 requests
0–49
50–89
90–100

Architecture Stack

Monolithic
⚙️ SSR
Frontend
Styling
Bootstrap
CMS
PrestaShop
Infrastructure
Hosting
Web4U s.r.o

Technology Stack

9 Technologies Detected

Libraries

2
jQueryv2.1.1
jQuery UI

CSS Frameworks

2
Bootstrapv3.4.1
Tailwind CSS

Analytics

2
Google Analytics
Google Analytics 4

Tag Managers

1
Google Tag Manager

Customer Support

1
Intercom

Web Servers

1
OpenResty

SEO Analysis

C61/100
15
11
1
Meta Tags13/15
Content11/12
Headings8/8
Technical10/25
E-E-A-T3/7
Images2/7
Links5/5
URL5/5
Social0/5
Freshness0/4
Mobile1/4
Indexability3/3
W
web4u.czweb4u.cz

Profesionální webové služby pro vaši online prezentaci - Web4U

Web4u nabízí kvalitní webové služby, které umožní vaší online prezentaci posunout se o úroveň výš. Vyberte si z registrace domény, hostingu a dalších nabízen...

Description truncated.
Title Length62 chars

Recommended: 50-60 chars (~374px / 580px)

Description Length168 chars

Recommended: 120-160 chars

Issues (1)

  • • Missing viewport meta tag — page may not be mobile-friendly (Google uses mobile-first indexing)

12 issues found

Upgrade to view details

Crawlability

Sitemap

Type: standard

118 URLs

robots.txt

15 rules

Sitemap reference found

Allows all crawlers

Local SEO

Local Search Readiness

0/100
Poor
15 2

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

Sponsored

AI & LLM Readiness

D42/100
Bot Access
20/25
Machine Read.
11/25
Schema Data
0/25
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:10%
Words:825
Token eff.:Optimal
Sections/1K:21.8

Structured Data

No Schema

Citation Readiness

Opening Summary16w
Descriptive Headingsavg 3.3w
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...
Upgrade to view recommendations

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.
C
61/100
9
Passed
5
Critical
2
Warnings
Images & Alt Text
10/20
Checks if images have descriptive alt text for screen readers and visually impaired users.
Semantic Structure
11/20
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
11/15
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.
4 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.
42/100
A
73 mg
CO₂e / view
588.0 KB
Page Weight
80%
Cleaner Than
New Visitor
83 mg
vs
Returning (cached)
42 mg
Annual (10K/mo)
8.7 kg
Emission Segments
Data Center
16 mg
Network
18 mg
Device
39 mg
Resource Breakdown
JavaScript
102.7 KB
Images
31.2 KB
CSS
444.0 KB
HTML
10.2 KB
Green Hosting Not Verified
Web4U s.r.o
5 recommendations
  • •Carbon footprint recommendation preview...
Upgrade to view recommendations
C

Security Score

66%Fair
Interactive

HTTPS

No WAF

73d

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

16.04.2026

Valid Until

15.07.2026

Subject Alternative Names (2)

web4u.czwww.web4u.cz

SHA-256 Fingerprint

82:16:1A:4C:23:87:CF:8E:97:C9:00:F3:74:EC:05:3D:D5:AE:3D:88...

Top Recommendations

Security recommendation preview

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Upgrade to view header details

HTTP Headers

Developer Console

cache-control
🔴 No Cache(no-store, no-cache, must-revalidate)
content-encoding
📦 Gzip(gzip)
content-length
10137
content-security-policy
frame-ancestors 'self';
content-type
text/html; charset=utf-8
date
Sun, 03 May 2026 05:17:08 GMT
Good Warning Issue

Email Infrastructure

Custom Mail Server

Score

100

SPF
DKIM
DMARC

DMARC Policy

Reject (Strictest)

MX Records (1)

mx.web4u.cz

Domain Information

web4u.cz

Domain Age
25y 4m

Created

12.12.2000

Expires

16.12.2026

Last Updated

17.04.2023

Registrar

REG-WEB4U

DNSSEC
Not Enabled

Privacy & Compliance

Cookie Consent Banner
Privacy Policy
Terms of Service

GDPR Indicators

Cookie consent banner detected
Data Protection Officer mentioned

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.
F
39/100
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.
4 recommendations
  • •Mobile compatibility recommendation preview...
Upgrade to view recommendations

Typography & Readability

MyriadProLight + MyriadProRegular

WCAG Partial
50/100
Readability
/30
12/30

12px · LH 1.60

Hierarchy
/20
16/20

4x ratio · ✓ H1→H6

WCAG
/25
15/25

1:1 min contrast

Performance
/25
7/25

3 fonts · 9 req

Heading Font

MyriadProLight

Sans48px

Body Font

MyriadProRegular

Sans12px

Contrast Ratio

1:1

22 issues

Reading Comfort

~177 CPL

Too wide
48px
h1
38px
h2
14px
h3
16px
h4
12px
p

❌ Critical: 12px body text is too small. Minimum 14px, recommend 16px+.

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

❌ Very long lines: ~177 chars/line causes eye strain. Add max-width constraint.

❌ Very complex text: Flesch score 27/100. Consider shorter sentences and simpler words.

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

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

Buy on MyFontsFlesch 27

Color Palette

8 unique colors
Light
#ffffff
Background· 50.3%
#d4e4eb
Secondary· 18.9%
#ebf0f1
Secondary· 7.4%
#66b4ca
Primary· 7.2%
#a5cbd6
Secondary· 5.8%
#5ca09f
Secondary· 4%
#7d6f4e
Secondary· 3.5%
#cfcbb7
Secondary· 2.7%

Business & Marketing Stack

4 Tools Detected

Advanced

Customer Support

1
IntercomMid-Market

Live chat and helpdesk tools

Behavior Analytics

2
Google Tag ManagerFree
Google AnalyticsFree

User behavior and product analytics

Advertising

1
Reddit PixelMid-Market

Ad platforms and retargeting pixels

3

Categories

4

Total Tools

0

Enterprise

2

Mid-Market

Assessment: Well-developed marketing technology stack

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Scripts & Styles

25 Resources

20
Scripts
5
Styles
9
Async
0
Defer

Top Script Sources

local(10)googletagmanager.com(4)widget.intercom.io(1)redditstatic.com(1)a.quora.com(1)

Website Identity

web4u.cz

25 years old
Location detected: 🇨🇿 Czech Republicvia tld
REG-WEB4U

Social Profiles

Facebook

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Last analyzed: 03 May 2026 at 05:17

Historical Analysis & Change Tracking