learnku.com

https://learnku.com· First analyzed 04 May 2026· Updated 04 May 2026

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learnku.com

Mobile

Sponsored

Hosting Provider

Shanghai UCloud Information Technology Company Limited

IP Address

117.50.42.115

Site Location

🇨🇳 Chinavia ip

Server Location

🇨🇳 Beijing, China

ASN

AS23724

Organization

Shanghai UCloud Information Technology Company Limited

Server

Nginx

Nameservers

dns7.hichina.com.dns8.hichina.com.f1g1ns1.dnspod.net.

Performance

Core Web Vitals

Weight

First Contentful Paint

6.6 s10%

Speed Index

8.6 s10%

Largest Contentful Paint

—25%

Total Blocking Time

0.0 ms30%

Cumulative Layout Shift

0.00025%

17 KB

79 requests

0–49

50–89

90–100

Architecture Stack

Monolithic

⚙️ SSR

Infrastructure

Hosting

Shanghai UCloud Information Technology Company Limited

Technology Stack

3 Technologies Detected

Frameworks

Vue.js

CSS Frameworks

Tailwind CSS

Web Servers

Nginxv1.27.1

SEO Analysis

D50/100

Meta Tags5/15

Content9/12

Headings1/8

Technical15/25

E-E-A-T3/7

Images2/7

Links4/5

URL5/5

Social0/5

Freshness0/4

Mobile3/4

Indexability3/3

learnku.comlearnku.com

LearnKu 终身编程者的知识社区

专为终身学习者定制的编程知识社区

Title Length18 chars

Recommended: 50-60 chars (~111px / 580px)

Description Length16 chars

Recommended: 120-160 chars

Issues (2)

• Missing H1 tag — every page should have exactly one H1
• Most images missing alt text (121/121) — critical for accessibility and SEO

11 issues found

Upgrade to view details

Crawlability

Sitemap

Type: standard

619 URLs

robots.txt

5 rules

Sitemap reference found

Local SEO

Local Search Readiness

6/100

Poor

2 13 2

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

Sponsored

AI & LLM Readiness

F33/100

Bot Access

20/25

Machine Read.

8/25

Schema Data

0/25

Citation

5/25

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:394

Token eff.:Optimal

Sections/1K:2.5

Depth:1/5

Structured Data

No Schema

Citation Readiness

Opening Summary

Descriptive Headingsavg 1w

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...

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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.

49/100

Passed

Critical

Warnings

Images & Alt Text

5/20

Checks if images have descriptive alt text for screen readers and visually impaired users.

Semantic Structure

9/20

Evaluates proper use of HTML5 semantic elements (header, nav, main, footer) and heading hierarchy.

Forms & Inputs

3/15

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

6/15

Checks correct use of WAI-ARIA attributes (roles, states, properties) for assistive technologies.

4 recommendations

•Accessibility recommendation preview...

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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.

55/100

A+

2 mg

CO₂e / view

16.7 KB

Page Weight

95%

Cleaner Than

New Visitor

2 mg

Returning (cached)

1 mg

Annual (10K/mo)

252 g

Emission Segments

Data Center

<0.001 g

Network

<0.001 g

Device

1 mg

Resource Breakdown

HTML

16.7 KB

Green Hosting Not Verified

Shanghai UCloud Information Technology Company Limited

4 recommendations

•Carbon footprint recommendation preview...

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Security Score

0%Critical

Critical / Transactional

HTTPS

No WAF

32d

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/1.1

Valid From

08.03.2026

Valid Until

06.06.2026

Subject Alternative Names (1)

learnku.com

SHA-256 Fingerprint

EA:57:43:DB:E2:6F:33:94:8A:BE:B9:3A:A3:2C:9B:A3:06:29:38:D8...

Top Recommendations

Security recommendation preview

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HTTP Headers

Developer Console

cache-control

🔴 No Cache(no-cache, private)

connection

keep-alive

content-encoding

📦 Gzip(gzip)

content-type

text/html; charset=UTF-8

date

Mon, 04 May 2026 12:12:15 GMT

server

nginx/1.27.1

Good Warning Issue

Email Infrastructure

Custom Mail Server

Score

SPF

DKIM

DMARC

MX Records (2)

mxbiz1.qq.com

mxbiz2.qq.com

Domain Information

learnku.com

Domain Age

9y 7m

Created

01.10.2016

Expires

01.10.2027

Last Updated

19.02.2025

Registrar

Alibaba Cloud Computing (Beijing) Co., Ltd.

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.

54/100

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, maximum-scale=1, user-scalable=no

3 recommendations

•Mobile compatibility recommendation preview...

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Typography & Readability

Lato + Helvetica

WCAG Partial

51/100

Readability

/30

13/30

13px · LH 1.98

Hierarchy

/20

7/20

WCAG

/25

17/25

2.57:1 min contrast

Performance

/25

14/25

2 fonts

Heading Font

Lato

Sans

Body Font

Helvetica

Sans13px

Contrast Ratio

2.57:1

7 issues

Reading Comfort

~54 CPL

Optimal (45–75)

16px

15px

13px

❌ Critical: 13px body text is too small. Minimum 14px, recommend 16px+.

⚠️ Wide line spacing (1.98). 1.4–1.6 is optimal for body text.

✅ Optimal line length: ~54 chars/line (ideal 45–75 CPL).

❌ Very complex text: Flesch score 25/100. Consider shorter sentences and simpler words.

⚠️ Partial contrast: 7 elements below WCAG AA threshold (min 2.6:1).

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

Buy on MyFontsFlesch 25

Color Palette

6 unique colors

3.68:1 AA Large Light

#ffffff

Background· 58.3%

#8c828f

Other· 2.5%

#dae4e2

Secondary· 3.4%

Business & Marketing Stack

1 Tools Detected

Growing

Behavior Analytics

Google AnalyticsFree

User behavior and product analytics

Sponsored

Scripts & Styles

5 Resources

Scripts

Styles

Async

Defer

Top Script Sources

cdn.learnku.com(2)zz.bdstatic.com(1)

Website Identity

learnku.com

9 years old

Location detected: 🇨🇳 Chinavia ip

Alibaba Cloud Computing (Beijing) Co., Ltd.zh

Sponsored

Last analyzed: 04 May 2026 at 12:13

Historical Analysis & Change Tracking