Access isc.sjtu.edu.cn. Study@SJTU

name

value

score

weighting

FCP (First Contentful Paint)

Value1.5 s

95/100

10%

LCP (Largest Contentful Paint)

Value6.9 s

7/100

25%

SI (Speed Index)

Value4.7 s

69/100

10%

TBT (Total Blocking Time)

Value30 ms

100/100

30%

CLS (Cumulative Layout Shift)

Value0

100/100

15%

TTI (Time to Interactive)

Value3.8 s

90/100

10%

isc.sjtu.edu.cn

855 ms

Our browser made a total of 1 request to load all elements on the main page. We found that all of those requests were addressed to Isc.sjtu.edu.cn and no external sources were called. The less responsive or slowest element that took the longest time to load (855 ms) belongs to the original domain Isc.sjtu.edu.cn.

Content Size

446 B

After Optimization

198 B

In fact, the total size of Isc.sjtu.edu.cn main page is 446 B. This result falls within the top 5000 of lightweight and thus fast loading web pages. Only a small number of websites need less resources to load. HTML takes 446 B which makes up the majority of the site volume.

HTML Optimization

-56%

Potential reduce by 248 B

Original 446 B
After minification 260 B
After compression 198 B

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. This page needs HTML code to be minified as it can gain 186 B, which is 42% of the original size. It is highly recommended that content of this web page should be compressed using GZIP, as it can save up to 248 B or 56% of the original size.

Requests Now

After Optimization

Besides the initial HTML request, no CSS, Javascripts, AJAX or image files were requested in the course of web page rendering.

Accessibility Issues

These are opportunities to improve the legibility of your content.

High

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

These are opportunities to improve the interpretation of your content by users in different locales.

High

<html> element does not have a [lang] attribute

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.

High

Image elements do not have [alt] attributes

High

<input type="image"> elements do not have [alt] text

High

Form elements do not have associated labels

High

Links do not have a discernible name

These are opportunities to improve the experience of reading tabular or list data using assistive technology, like a screen reader.

High

Lists do not contain only <li> elements and script supporting elements (<script> and <template>).

Areas of Improvement

High

Does not use HTTPS

High

Includes front-end JavaScript libraries with known security vulnerabilities

Low

Ensure CSP is effective against XSS attacks

High

Displays images with incorrect aspect ratio

High

Serves images with low resolution

Low

Detected JavaScript libraries

High

Browser errors were logged to the console

Search Engine Optimization Advices

To appear in search results, crawlers need access to your app.

High

Links are not crawlable

Format your HTML in a way that enables crawlers to better understand your app’s content.

High

Image elements do not have [alt] attributes

Language and Encoding

Language Detected

EN
Language Claimed

ZH
Encoding

GB2312

Language claimed in HTML meta tag should match the language actually used on the web page. Otherwise Isc.sjtu.edu.cn can be misinterpreted by Google and other search engines. Our service has detected that English is used on the page, and it does not match the claimed Chinese language. Our system also found out that Isc.sjtu.edu.cn 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

isc.sjtu.edu.cn

Open Graph description is not detected on the main page of Isc SJTU. 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: