33.3 sec in total
1.4 sec
31.2 sec
693 ms
Visit class.cn now to see the best up-to-date Class content for China and also check out these interesting facts you probably never knew about class.cn
好课网是中国教育在线的在线学习平台,该平台面向学习者提供涵盖基础教育、高等教育以及行业培训等海量优质网络课程,汇聚各行业精英,你可以自由选择你所需的或者感兴趣的网络课程在线学习,好课网邀你一起来学习和分享!
Visit class.cnWe analyzed Class.cn page load time and found that the first response time was 1.4 sec and then it took 31.9 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 was 1 request timeout, which can generally increase the web page load time, as the browser stays idle while waiting for website response.
class.cn performance score
name
value
score
weighting
Value2.4 s
71/100
10%
Value4.6 s
35/100
25%
Value7.2 s
30/100
10%
Value10 ms
100/100
30%
Value0
100/100
15%
Value3.5 s
92/100
10%
1431 ms
682 ms
9289 ms
1024 ms
2008 ms
Our browser made a total of 88 requests to load all elements on the main page. We found that 68% of them (60 requests) were addressed to the original Class.cn, 18% (16 requests) were made to V2.data.class.cn and 3% (3 requests) were made to Stat.eol.cn. The less responsive or slowest element that took the longest time to load (19.8 sec) belongs to the original domain Class.cn.
Page size can be reduced by 682.6 kB (60%)
1.1 MB
451.2 kB
In fact, the total size of Class.cn main page is 1.1 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. 30% of websites need less resources to load. Images take 499.9 kB which makes up the majority of the site volume.
Potential reduce by 55.0 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 55.0 kB or 83% of the original size.
Potential reduce by 189.1 kB
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. Obviously, Class needs image optimization as it can save up to 189.1 kB or 38% of the original volume. The most popular and efficient tools for JPEG and PNG image optimization are Jpegoptim and PNG Crush.
Potential reduce by 280.6 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 280.6 kB or 75% of the original size.
Potential reduce by 157.9 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. Class.cn needs all CSS files to be minified and compressed as it can save up to 157.9 kB or 81% of the original size.
Number of requests can be reduced by 17 (20%)
84
67
The browser has sent 84 CSS, Javascripts, AJAX and image requests in order to completely render the main page of Class. We recommend that multiple CSS and JavaScript files should be merged into one by each type, as it can help reduce assets requests from 14 to 1 for JavaScripts and from 5 to 1 for CSS and as a result speed up the page load time.
main
1431 ms
basic.css
682 ms
layout.css
9289 ms
libs.css
1024 ms
jQuery_latest.min.js
2008 ms
jquery.raty.js
1036 ms
jquery.dragsort.js
1351 ms
lhgcore.lhgdialog.min.js
1315 ms
effect.js
2645 ms
login.js
1682 ms
public.js
1613 ms
libs.js
1988 ms
focus_img.js
1949 ms
stat.php
2982 ms
110051.js
5724 ms
default.css
300 ms
toppic_20160222.jpg
19842 ms
course_5272_298x150.jpg
11953 ms
course_106319_298x150.jpg
11946 ms
course_106372_298x150.jpg
11949 ms
course_8785_298x150.jpg
12579 ms
course_106157_298x150.png
13976 ms
course_106369_298x150.png
12581 ms
course_106999_298x150.jpg
12989 ms
course_107011_298x150.png
14820 ms
course_107001_298x150.jpg
14473 ms
course_105953_298x150.jpg
14166 ms
course_5626_298x150.jpg
13941 ms
course_103147_298x150.jpg
15735 ms
course_8588_298x150.jpg
15165 ms
course_7006_298x150.jpg
14901 ms
course_106259_298x150.jpg
15418 ms
course_103621_298x150.jpg
15438 ms
toppic_20160105.jpg
3651 ms
toppic_20150813.jpg
4519 ms
toppic_20150812.jpg
6960 ms
toppic_20150702.jpg
8704 ms
star_gray.png
8087 ms
star.png
8759 ms
star_ban.gif
4953 ms
huatu.jpg
5372 ms
tuxiaobei.jpg
7946 ms
dezhi.jpg
7758 ms
hujiang.jpg
8189 ms
landi.jpg
9213 ms
haoxue.jpg
9476 ms
zhonggong.jpg
9485 ms
gaodun.jpg
11717 ms
xingshuai.jpg
9210 ms
beifeng.jpg
10077 ms
18.jpg
10858 ms
zhike.jpg
10315 ms
hongcheng.jpg
10698 ms
jiandan.jpg
12117 ms
puming.jpg
11213 ms
woxue.jpg
11584 ms
zhengbao.jpg
13020 ms
xdf.jpg
13165 ms
logo.png
2758 ms
sina-t.jpg
632 ms
qq-t.jpg
637 ms
renren-t.jpg
641 ms
social-share-weixin.png
298 ms
social-share-weibo.png
300 ms
social-share-renren.png
635 ms
social-share-tengxun.png
638 ms
weixin_430x430.jpg
6804 ms
top-nav-bg.jpg
1812 ms
searchbar-bg.png
1923 ms
small-icons.png
2610 ms
course-title-alphabg.png
1890 ms
course-img-mask.png
2415 ms
course-info-border.jpg
2227 ms
four-spots.png
8443 ms
app-download-bg.png
8170 ms
buttons-orange-green.png
3273 ms
stat.htm
232 ms
core.php
1690 ms
h.js
8327 ms
hm.gif
385 ms
piwik.js
1685 ms
looyu.css
2291 ms
looyu.js
3400 ms
mysql.php
386 ms
ok.html
1560 ms
s
2654 ms
online.png
327 ms
loading.gif
627 ms
class.cn accessibility score
Contrast
These are opportunities to improve the legibility of your content.
Impact
Issue
Background and foreground colors do not have a sufficient contrast ratio.
Internationalization and localization
These are opportunities to improve the interpretation of your content by users in different locales.
Impact
Issue
<html> element does not have a [lang] attribute
Names and labels
These are opportunities to improve the semantics of the controls in your application. This may enhance the experience for users of assistive technology, like a screen reader.
Impact
Issue
Image elements do not have [alt] attributes
Links do not have a discernible name
class.cn best practices score
Trust and Safety
Impact
Issue
Does not use HTTPS
Includes front-end JavaScript libraries with known security vulnerabilities
Ensure CSP is effective against XSS attacks
User Experience
Impact
Issue
Displays images with incorrect aspect ratio
Serves images with low resolution
General
Impact
Issue
Detected JavaScript libraries
class.cn SEO score
Crawling and Indexing
To appear in search results, crawlers need access to your app.
Impact
Issue
robots.txt is not valid
Content Best Practices
Format your HTML in a way that enables crawlers to better understand your app’s content.
Impact
Issue
Image elements do not have [alt] attributes
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
Document uses legible font sizes
ZH
EN
UTF-8
Language claimed in HTML meta tag should match the language actually used on the web page. Otherwise Class.cn can be misinterpreted by Google and other search engines. Our service has detected that Chinese is used on the page, and it does not match the claimed English language. Our system also found out that Class.cn main page’s claimed encoding is utf-8. Use of this encoding format is the best practice as the main page visitors from all over the world won’t have any issues with symbol transcription.
class.cn
Open Graph description is not detected on the main page of Class. 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: