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slf4j.org

https://slf4j.org· First analyzed 30 Apr 2026· Updated 30 Apr 2026
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slf4j.org
Desktop screenshot of slf4j.org
Mobile screenshot of slf4j.org
Mobile

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Hosting Provider

Akenes

IP Address

159.100.250.151

Site Location

🇨🇭 Switzerlandvia ip

Server Location

🇨🇭 Zurich, Switzerland

ASN

AS61098

Organization

Akenes

Server

Apache

Nameservers

fran1.slf4j.org.exo1.slf4j.org.

Performance

86

Core Web Vitals

Weight

First Contentful Paint
1.7 s10%
Speed Index
2.2 s10%
Largest Contentful Paint
—25%
Total Blocking Time
0.0 ms30%
Cumulative Layout Shift
0.00025%
288 KB
19 requests
0–49
50–89
90–100

Architecture Stack

Monolithic
⚙️ SSR
Infrastructure
Hosting
Akenes

Technology Stack

3 Technologies Detected

CSS Frameworks

1
Tailwind CSS

Icon Libraries

1
Font Awesome

Web Servers

1
Apachev2.4.66

SEO Analysis

D45/100
12
9
2
Meta Tags4/15
Content9/12
Headings3/8
Technical10/21
E-E-A-T0/7
Images2/7
Links5/5
URL5/5
Social0/5
Freshness0/4
Mobile4/4
Indexability3/3
S
slf4j.orgslf4j.org

SLF4J

No description available for this page.

Title Length5 chars

Recommended: 50-60 chars (~31px / 580px)

Description Length0 chars

Recommended: 120-160 chars

Issues (2)

  • • Missing meta description — important for click-through rates in SERPs
  • • Missing H1 tag — every page should have exactly one H1

11 issues found

Upgrade to view details

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.
2/25
Schema Data
0/25
Citation
6/25

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:25%
Words:261
Token eff.:Too Short
Sections/1K:7.7

Structured Data

No Schema

Citation Readiness

Opening Summary12w
Descriptive Headingsavg 5w
Canonical URL
Open Graph0/3
Twitter Card0/3
Language Tag
Publish Date
Author Info
Lists
Tables
TL;DR / Summary
About Page Link
Recommendations (11)
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.
D
57/100
7
Passed
6
Critical
0
Warnings
Images & Alt Text
10/20
Checks if images have descriptive alt text for screen readers and visually impaired users.
Semantic Structure
7/20
Evaluates proper use of HTML5 semantic elements (header, nav, main, footer) and heading hierarchy.
Forms & Inputs
15/15
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.
3 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.
76/100
A+
29 mg
CO₂e / view
288.3 KB
Page Weight
90%
Cleaner Than
New Visitor
33 mg
vs
Returning (cached)
17 mg
Annual (10K/mo)
3.5 kg
Emission Segments
Data Center
1 mg
Network
9 mg
Device
19 mg
Resource Breakdown
JavaScript
78.5 KB
Images
33.1 KB
CSS
175.5 KB
HTML
1.3 KB
Green Hosting Verified
Hostinger
GWF Verified
2 recommendations
  • •Carbon footprint recommendation preview...
Upgrade to view recommendations
B

Security Score

71%Good
Static / Informational

HTTPS

No WAF

69d

Certificate Details

Type

Domain Validated (DV)

Certificate Authority

Let's Encrypt

Key Algorithm

ECDSA (secp256r1) (256 bit)

Signature

ECDSA with SHA-384

TLS Version

TLSv1.3

HTTP Protocol

HTTP/1.1

Valid From

10.04.2026

Valid Until

09.07.2026

Subject Alternative Names (2)

slf4j.orgwww.slf4j.org

SHA-256 Fingerprint

7E:3A:90:75:10:CE:AB:62:93:D6:61:01:3E:14:58:34:55:4A:7F:2A...

Recommendations

Security recommendation preview

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HTTP Headers

Developer Console

accept-ranges
bytes
connection
Keep-Alive
content-encoding
📦 Gzip(gzip)
content-length
986
content-type
text/html
date
Thu, 30 Apr 2026 04:45:20 GMT
Good Warning Issue

Email Infrastructure

Custom Mail Server

Score

0

SPF
DKIM
DMARC

Domain Information

slf4j.org

Domain Age
21 years

Created

14.04.2005

Expires

14.04.2029

Last Updated

27.08.2025

Registrar

NameCheap, Inc.

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
49/100
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
width=device-width, initial-scale=1
3 recommendations
  • •Mobile compatibility recommendation preview...
Upgrade to view recommendations

Typography & Readability

Verdana

WCAG Partial
59/100
Readability
/30
21/30

16px · LH --

Hierarchy
/20
8/20
WCAG
/25
17/25

2.71:1 min contrast

Performance
/25
13/25

1 font · 1 req

Heading Font

Verdana

Sans

Body Font

Verdana

Sans16px

Contrast Ratio

2.71:1

31 issues

Reading Comfort

~39 CPL

Narrow lines
24px
h2
18px
h3
16px
p

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

⚠️ Hard to read: Flesch score 43/100. Simplify sentences for wider reach.

⚠️ Partial contrast: 31 elements below WCAG AA threshold (min 2.7:1).

❌ Missing H1: Every page should have exactly one H1 element for SEO and accessibility.

✅ Lean font stack: 1 font families keeps load times fast.

⚠️ Missing font-display: swap — users may see invisible text while fonts load (FOIT).

Buy on MyFontsFlesch 43

Color Palette

8 unique colors
4.03:1 AA Large Light
#ffffff
Background· 85.8%
#7f7e83
Other· 2.3%
#c1c8cc
Primary· 2.4%
#dfd5ca
Secondary· 1.5%

Business & Marketing Stack

2 Tools Detected

Growing

Behavior Analytics

1
Google AnalyticsFree

User behavior and product analytics

Social Media

1
Twitter/X WidgetsFree

Social widgets and sharing tools

2

Categories

2

Total Tools

0

Enterprise

0

Mid-Market

Assessment: Growing marketing technology adoption

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Scripts & Styles

13 Resources

7
Scripts
6
Styles
0
Async
0
Defer

Top Script Sources

js(4)templates(2)common(1)

Website Identity

slf4j.org

21 years old
Location detected: 🇨🇭 Switzerlandvia ip
NameCheap, Inc.en

Social Profiles

GitHub

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Last analyzed: 30 Apr 2026 at 04:45

Historical Analysis & Change Tracking