Tools & Wizards About Us
developer.51cto.com screenshot

Report Summary

  • 33

    Performance

    Renders faster than
    53% of other websites

  • 74

    Accessibility

    Visual factors better than
    that of 41% of websites

  • 83

    Best Practices

    More advanced features
    available than in
    56% of websites

  • 100

    SEO

    Google-friendlier than
    95% of websites

developer.51cto.com

开发-51CTO.COM-中国知名的数字化人才学习平台和技术社区

Page Load Speed

47.4 sec in total

First Response

3 sec

Resources Loaded

41.2 sec

Page Rendered

3.2 sec

developer.51cto.com screenshot

About Website

Visit developer.51cto.com now to see the best up-to-date Developer 51CTO content for China and also check out these interesting facts you probably never knew about developer.51cto.com

51CTO-向开发者分享前端开发、后端开发、游戏开发、测试开发、开发工具、中台与架构、VR与AR等相关软件开发的技术资讯与实践案例。

Visit developer.51cto.com

Key Findings

We analyzed Developer.51cto.com page load time and found that the first response time was 3 sec and then it took 44.4 sec to load all DOM resources and completely render a web page. This is a poor result, as 95% of websites can load faster. Unfortunately, there were 2 request timeouts, which can generally increase the web page load time, as the browser stays idle while waiting for website response.

Performance Metrics

developer.51cto.com performance score

33

Measured Metrics

name

value

score

weighting

FCP (First Contentful Paint)

Value17.9 s

0/100

10%

LCP (Largest Contentful Paint)

Value20.1 s

0/100

25%

SI (Speed Index)

Value22.5 s

0/100

10%

TBT (Total Blocking Time)

Value470 ms

60/100

30%

CLS (Cumulative Layout Shift)

Value0

100/100

15%

TTI (Time to Interactive)

Value21.1 s

1/100

10%

Network Requests Diagram

developer.51cto.com

2982 ms

global.css

2034 ms

style2.css

1102 ms

allmobilize.min.js

13852 ms

jquery.min.js

2865 ms

Our browser made a total of 93 requests to load all elements on the main page. We found that 1% of them (1 request) were addressed to the original Developer.51cto.com, 18% (17 requests) were made to Images.51cto.com and 17% (16 requests) were made to 51cto.com. The less responsive or slowest element that took the longest time to load (20.5 sec) relates to the external source I2.51cto.com.

Page Optimization Overview & Recommendations

Page size can be reduced by 385.9 kB (19%)

Content Size

2.0 MB

After Optimization

1.7 MB

  • HTML
  • Images
  • JavaScript
  • CSS

In fact, the total size of Developer.51cto.com main page is 2.0 MB. This result falls beyond the top 1M of websites and identifies a large and not optimized web page that may take ages to load. 25% of websites need less resources to load. Images take 1.6 MB which makes up the majority of the site volume.

HTML Optimization

-80%

Potential reduce by 75.2 kB

  • Original 94.4 kB
  • After minification 85.9 kB
  • After compression 19.2 kB

HTML content can be minified and compressed by a website’s server. The most efficient way is to compress content using GZIP which reduces data amount travelling through the network between server and browser. HTML code on this page is well minified. It is highly recommended that content of this web page should be compressed using GZIP, as it can save up to 75.2 kB or 80% of the original size.

Image Optimization

-6%

Potential reduce by 93.3 kB

  • Original 1.6 MB
  • After minification 1.5 MB

Image size optimization can help to speed up a website loading time. The chart above shows the difference between the size before and after optimization. Developer 51CTO images are well optimized though.

JavaScript Optimization

-63%

Potential reduce by 205.3 kB

  • Original 325.7 kB
  • After minification 316.2 kB
  • After compression 120.4 kB

It’s better to minify JavaScript in order to improve website performance. The diagram shows the current total size of all JavaScript files against the prospective JavaScript size after its minification and compression. It is highly recommended that all JavaScript files should be compressed and minified as it can save up to 205.3 kB or 63% of the original size.

CSS Optimization

-77%

Potential reduce by 12.2 kB

  • Original 15.8 kB
  • After minification 13.8 kB
  • After compression 3.7 kB

CSS files minification is very important to reduce a web page rendering time. The faster CSS files can load, the earlier a page can be rendered. Developer.51cto.com needs all CSS files to be minified and compressed as it can save up to 12.2 kB or 77% of the original size.

Requests Breakdown

Number of requests can be reduced by 38 (47%)

Requests Now

81

After Optimization

43

  • AJAX
  • Images
  • JavaScript
  • CSS

The browser has sent 81 CSS, Javascripts, AJAX and image requests in order to completely render the main page of Developer 51CTO. We recommend that multiple CSS and JavaScript files should be merged into one by each type, as it can help reduce assets requests from 26 to 1 for JavaScripts and as a result speed up the page load time.

Network Requests Diagram

developer.51cto.com

developer.51cto.com

2982 ms

global.css

global.css

2034 ms

style2.css

style2.css

1102 ms

allmobilize.min.js

allmobilize.min.js

13852 ms

jquery.min.js

jquery.min.js

2865 ms

nav_js.js

nav_js.js

2023 ms

move.js

move.js

2024 ms

index_1_down.js

index_1_down.js

2035 ms

art_master_top.css

art_master_top.css

2034 ms

head_art_zt.js

head_art_zt.js

5947 ms

c.js

c.js

1109 ms

copy_right.js

copy_right.js

1850 ms

count.js

count.js

918 ms

ad01.js

ad01.js

1018 ms

ad02.js

ad02.js

1110 ms

ad03.js

ad03.js

1164 ms

ad.js

ad.js

1188 ms

index.php

index.php

2804 ms

logo.png

logo.png

262 ms

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wKiom1cHB_Cjmr3RAAEp_r79pDM229.jpg

1929 ms

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1781 ms

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wKiom1cEmSLTJ598AACCPg-dOwQ394.jpg

1385 ms

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1416 ms

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1765 ms

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12ba2840589ad28fba21471c3dd578837e48f6.jpg

1091 ms

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wKiom1bqP3qDaTX6AAEf5tKnttw355.png

84 ms

down.51cto.com

down.51cto.com

4292 ms

rside_weixin.jpg

rside_weixin.jpg

15618 ms

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2163 ms

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1929 ms

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553 ms

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wKioL1bqGuHitywHAAAguE6Ozww803.jpg

813 ms

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wKiom1apfgCiB1ANAABSoJNlvG8904.jpg

80 ms

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79 ms

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wKiom1bpAj-wkvDQAABshUy9xc0503.jpg

1399 ms

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1400 ms

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wKioL1cEuGrRDvPXAAAgzjOcKVU481.gif

812 ms

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1757 ms

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810 ms

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wKioL1bG5OXAlOHuAABkIc9OeQE287.jpg

1387 ms

sublogo.png

sublogo.png

267 ms

1.png

1.png

273 ms

2.png

2.png

270 ms

3.png

3.png

271 ms

4.png

4.png

265 ms

5.png

5.png

486 ms

top_bg_xian.gif

top_bg_xian.gif

574 ms

top_bg.gif

top_bg.gif

1026 ms

top_shequ.gif

top_shequ.gif

1061 ms

51.gif

51.gif

487 ms

nav_ico1.gif

nav_ico1.gif

487 ms

143749870.gif

143749870.gif

499 ms

navbg.jpg

navbg.jpg

12230 ms

ajs.php

ajs.php

918 ms

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20488 ms

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1681 ms

lg.php

lg.php

1909 ms

wKioL1cGLqaTa0u6AAAV2T34xLs348.jpg

wKioL1cGLqaTa0u6AAAV2T34xLs348.jpg

388 ms

select_bottom.png

select_bottom.png

556 ms

line622.jpg

line622.jpg

529 ms

li_bg_square.jpg

li_bg_square.jpg

528 ms

eduplay.png

eduplay.png

529 ms

linebg.jpg

linebg.jpg

919 ms

tabbg01.jpg

tabbg01.jpg

18814 ms

tabbg02.jpg

tabbg02.jpg

4227 ms

listbg.gif

listbg.gif

1090 ms

a5ad7b020d9e075a92104636daa4837f1d5232.jpg

a5ad7b020d9e075a92104636daa4837f1d5232.jpg

19816 ms

IDG.CN_B2B_51cto.com;sz=960x90;ord=389495249837636

IDG.CN_B2B_51cto.com;sz=960x90;ord=389495249837636

41 ms

kcbm

kcbm

785 ms

h.js

h.js

1912 ms

analytics.js

analytics.js

16 ms

collect

collect

24 ms

collect

collect

87 ms

kcbm

kcbm

705 ms

adPic.new.20150909.min.js

adPic.new.20150909.min.js

78 ms

bot-patch.min.js

bot-patch.min.js

98 ms

click.min.js

click.min.js

99 ms

adx.php

adx.php

897 ms

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74 ms

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116 ms

21.gif

21.gif

876 ms

hm.gif

hm.gif

474 ms

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89 ms

adjs.php

adjs.php

962 ms

ajs.php

ajs.php

852 ms

ajs.php

ajs.php

841 ms

sm.min.js

sm.min.js

5604 ms

o.htm

o.htm

1098 ms

hm.gif

hm.gif

926 ms

wh.js

wh.js

839 ms

ac.js

ac.js

584 ms

fp.htm

fp.htm

808 ms

fp.htm

fp.htm

406 ms

Accessibility Review

developer.51cto.com accessibility score

74

Accessibility Issues

Contrast

These are opportunities to improve the legibility of your content.

Impact

Issue

High

Background and foreground colors do not have a sufficient contrast ratio.

Best practices

These items highlight common accessibility best practices.

Impact

Issue

High

[user-scalable="no"] is used in the <meta name="viewport"> element or the [maximum-scale] attribute is less than 5.

Best Practices

developer.51cto.com best practices score

83

Areas of Improvement

Trust and Safety

Impact

Issue

High

Does not use HTTPS

High

Includes front-end JavaScript libraries with known security vulnerabilities

Low

Ensure CSP is effective against XSS attacks

General

Impact

Issue

Low

Detected JavaScript libraries

SEO Factors

developer.51cto.com SEO score

100

Search Engine Optimization Advices

Mobile Friendly

Make sure your pages are mobile friendly so users don’t have to pinch or zoom in order to read the content pages. [Learn more](https://developers.google.com/search/mobile-sites/).

Impact

Issue

High

Document uses legible font sizes

Language and Encoding

  • Language Detected

    ZH

  • Language Claimed

    N/A

  • Encoding

    GB2312

Language claimed in HTML meta tag should match the language actually used on the web page. Otherwise Developer.51cto.com can be misinterpreted by Google and other search engines. Our service has detected that Chinese is used on the page, and neither this language nor any other was claimed in <html> or <meta> tags. Our system also found out that Developer.51cto.com main page’s claimed encoding is gb2312. Changing it to UTF-8 can be a good choice, as this format is commonly used for encoding all over the web and thus their visitors won’t have any troubles with symbol transcription or reading.

Social Sharing Optimization

developer.51cto.com

Open Graph description is not detected on the main page of Developer 51CTO. Lack of Open Graph description can be counter-productive for their social media presence, as such a description allows converting a website homepage (or other pages) into good-looking, rich and well-structured posts, when it is being shared on Facebook and other social media. For example, adding the following code snippet into HTML <head> tag will help to represent this web page correctly in social networks: