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o-seznam.cz

https://o-seznam.cz· First analyzed 02 May 2026· Updated 02 May 2026
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o-seznam.cz
Desktop screenshot of o-seznam.cz
Mobile screenshot of o-seznam.cz
Mobile

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Hosting Provider

Seznam - II

IP Address

77.75.78.9

Site Location

🇨🇿 Czech Republicvia tld

Server Location

🇨🇿 Prague, Czechia

ASN

AS43037

Server

Envoy

Nameservers

ams.seznam.cz.ans.seznam.cz.

Performance

100

Core Web Vitals

Weight

First Contentful Paint
515 ms10%
Speed Index
670 ms10%
Largest Contentful Paint
—25%
Total Blocking Time
0.0 ms30%
Cumulative Layout Shift
0.00025%
593 KB
44 requests

Image Optimization

Lazy LoadResponsive
0–49
50–89
90–100

Architecture Stack

Monolithic
⚙️ SSR
WordPress
cms
Seznamv1.4.11Custom
by Jan Bien

Progressive Web App

Web ManifestApple Touch IconTheme Color

Technology Stack

5 Technologies Detected

Libraries

1
jQueryv3.7.1

UI Components

1
Fancybox

CSS Frameworks

1
Tailwind CSS

Analytics

1
Google Analytics

Tag Managers

1
Google Tag Manager

SEO Analysis

B76/100
24
5
1
Meta Tags9/15
Content8/12
Headings7/8
Technical25/25
E-E-A-T2/7
Images3/7
Links5/5
URL5/5
Social5/5
Freshness0/4
Mobile4/4
Indexability3/3
O
o-seznam.czo-seznam.cz

O Seznamu

Jsme česká internetová jednička se zálibou v technologiích a datech. Máme vlastní datová centra a provozujeme přes 30 služeb, o které se stará více než 1 600…

Title Length9 chars

Recommended: 50-60 chars (~61px / 580px)

Description Length158 chars

Recommended: 120-160 chars

Issues (1)

  • • Most images missing alt text (10/13) — critical for accessibility and SEO

6 issues found

Upgrade to view details

Crawlability

Sitemap

Type: index

27 URLs

27 sub-sitemaps

robots.txt

5 rules

Sitemap reference found

Local SEO

Local Search Readiness

16/100
Poor
4 14

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

D52/100
Bot Access
20/25
Machine Read.
13/25
Schema Data
7/25
Citation
12/25

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:314
Token eff.:Optimal
Sections/1K:19.1
Depth:1/5

Structured Data

3 JSON-LD
Organization×1.1WebSiteBreadcrumbList
sameAs entity links

Citation Readiness

Opening Summary39w
Descriptive Headingsavg 1.3w
Canonical URL
Open Graph3/3
Twitter Card3/3
Language Tag
Publish Date
Author Info
Lists
Tables
TL;DR / Summary
About Page Link
Recommendations (7)
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.
A
80/100
13
Passed
2
Critical
1
Warnings
Images & Alt Text
20/20
Checks if images have descriptive alt text for screen readers and visually impaired users.
Semantic Structure
17/20
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
7/15
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.
62/100
A
73 mg
CO₂e / view
592.6 KB
Page Weight
80%
Cleaner Than
New Visitor
84 mg
vs
Returning (cached)
42 mg
Annual (10K/mo)
8.8 kg
Emission Segments
Data Center
16 mg
Network
18 mg
Device
39 mg
Resource Breakdown
JavaScript
63.0 KB
Images
175.0 KB
CSS
13.8 KB
Fonts
319.3 KB
HTML
21.4 KB
Green Hosting Not Verified
Seznam - II
4 recommendations
  • •Carbon footprint recommendation preview...
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F

Security Score

21%Critical
Interactive

HTTPS

No WAF

69d

Certificate Details

Type

Domain Validated (DV)

Certificate Authority

Let's Encrypt

Key Algorithm

RSA (4096 bit)

Signature

SHA-256 with RSA

TLS Version

TLSv1.3

HTTP Protocol

HTTP/2

Valid From

12.04.2026

Valid Until

11.07.2026

Subject Alternative Names (1)

o-seznam.cz

SHA-256 Fingerprint

AF:C7:A4:E9:E7:5C:09:25:30:64:BB:B0:37:76:80:01:1F:EA:4D:E4...

Top Recommendations

Security recommendation preview

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HTTP Headers

Developer Console

accept-ranges
bytes
cache-control
🟡 3s(max-age=3, must-revalidate)
content-encoding
📦 Gzip(gzip)
content-length
21660
content-type
text/html; charset=UTF-8
date
Sat, 02 May 2026 20:02:23 GMT
Good Warning Issue

Email Infrastructure

Custom Mail Server

Score

65

SPF
DKIM
DMARC

DMARC Policy

None (Monitor Only)

MX Records (2)

9e8bf2e009a3d4d9.mx1.emailprofi.seznam.cz
9e8bf2e009a3d4d9.mx2.emailprofi.seznam.cz

Domain Information

o-seznam.cz

Domain Age
2y 8m

Created

13.08.2023

Expires

12.08.2026

Last Updated

05.06.2024

Registrar

REG-SEZNAM

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.
A
84/100
Mobile Friendly41 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
1 recommendation
  • •Mobile compatibility recommendation preview...
Upgrade to view recommendations

Typography & Readability

Inter

WCAG Partial
75/100
Readability
/30
23/30

18px · LH 1.50

Hierarchy
/20
17/20

3.11x ratio

WCAG
/25
15/25

2.51:1 min contrast

Performance
/25
20/25

1 font · 1 req

Heading Font

Inter

Sans56px

Body Font

Inter

Sans18px

Contrast Ratio

2.51:1

3 issues

Reading Comfort

~36 CPL

Narrow lines
56px
h1
24px
h2
20px
h4
18px
p

✅ Excellent readability: 18px body text is ideal for all devices.

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

⚠️ Hard to read: Flesch score 35/100. Simplify sentences for wider reach.

⚠️ Partial contrast: 3 elements below WCAG AA threshold (min 2.5:1).

⚠️ Minor heading issue: 1 level skip(s) detected. Maintain sequential order for screen readers.

✅ Strong hierarchy: Headlines are 3.1x larger than body text.

Buy on MyFontsFluid Type (rem)Flesch 35

Color Palette

10 unique colors
4.67:1 AA Dark
#6c7581
Secondary· 26%
#ffffff
Background· 16.099999999999998%
#cc0000
Primary· 0%
#525e6a
Secondary· 5.6%
#1b232c
Secondary· 5.1%

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

19 Resources

14
Scripts
5
Styles
9
Async
4
Defer

Top Script Sources

o-seznam.cz(8)h.seznam.cz(3)googletagmanager.com(2)ssp.seznam.cz(1)

Website Identity

Seznam

Organization

Jsme česká internetová jednička se zálibou v technologiích a datech. Máme vlastní datová centra a provozujeme přes 30 služeb, o které se stará více než 1 600…

o-seznam.cz/
2 years old
Location detected: 🇨🇿 Czech Republicvia tld
REG-SEZNAMcs-CZ

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Last analyzed: 02 May 2026 at 20:02

Historical Analysis & Change Tracking