15.4 sec in total
703 ms
11.7 sec
2.9 sec
Click here to check amazing Chandra Harvard content for United States. Otherwise, check out these important facts you probably never knew about chandra.harvard.edu
NASA's sophisticated telescope is specially designed to detect X-ray emission from very hot regions of the Universe.
Visit chandra.harvard.eduWe analyzed Chandra.harvard.edu page load time and found that the first response time was 703 ms and then it took 14.7 sec to load all DOM resources and completely render a web page. This is a poor result, as 90% of websites can load faster.
chandra.harvard.edu performance score
name
value
score
weighting
Value5.2 s
8/100
10%
Value7.3 s
5/100
25%
Value54.4 s
0/100
10%
Value83,530 ms
0/100
30%
Value0
100/100
15%
Value106.4 s
0/100
10%
703 ms
140 ms
141 ms
178 ms
141 ms
Our browser made a total of 176 requests to load all elements on the main page. We found that 68% of them (119 requests) were addressed to the original Chandra.harvard.edu, 11% (19 requests) were made to Live.staticflickr.com and 4% (7 requests) were made to Youtube.com. The less responsive or slowest element that took the longest time to load (3.2 sec) relates to the external source Logs1.smithsonian.museum.
Page size can be reduced by 714.4 kB (20%)
3.6 MB
2.9 MB
In fact, the total size of Chandra.harvard.edu main page is 3.6 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. 85% of websites need less resources to load and that’s why Accessify’s recommendations for optimization and resource minification can be helpful for this project. Images take 2.8 MB which makes up the majority of the site volume.
Potential reduce by 121.7 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 121.7 kB or 84% of the original size.
Potential reduce by 161.6 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. Chandra Harvard images are well optimized though.
Potential reduce by 77.4 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 77.4 kB or 32% of the original size.
Potential reduce by 353.7 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. Chandra.harvard.edu needs all CSS files to be minified and compressed as it can save up to 353.7 kB or 85% of the original size.
Number of requests can be reduced by 37 (22%)
171
134
The browser has sent 171 CSS, Javascripts, AJAX and image requests in order to completely render the main page of Chandra Harvard. We recommend that multiple CSS and JavaScript files should be merged into one by each type, as it can help reduce assets requests from 32 to 1 for JavaScripts and from 7 to 1 for CSS and as a result speed up the page load time.
chandra.harvard.edu
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cxcpub_topmenu.css
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make.png
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chandra.harvard.edu 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.
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
Links do not have a discernible name
chandra.harvard.edu 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
Browser errors were logged to the console
Issues were logged in the Issues panel in Chrome Devtools
chandra.harvard.edu SEO score
Content Best Practices
Format your HTML in a way that enables crawlers to better understand your app’s content.
Impact
Issue
Links do not have descriptive text
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
Tap targets are not sized appropriately
EN
EN
UTF-8
Language claimed in HTML meta tag should match the language actually used on the web page. Otherwise Chandra.harvard.edu can be misinterpreted by Google and other search engines. Our service has detected that English is used on the page, and it matches the claimed language. Our system also found out that Chandra.harvard.edu 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.
chandra.harvard.edu
Open Graph description is not detected on the main page of Chandra Harvard. 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: