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Report Summary

  • 49

    Performance

    Renders faster than
    68% of other websites

  • 96

    Accessibility

    Visual factors better than
    that of 89% of websites

  • 92

    Best Practices

    More advanced features
    available than in
    81% of websites

  • 100

    SEO

    Google-friendlier than
    95% of websites

books.coreknowledge.org

Core Knowledge Foundation | Building knowledge and community

Page Load Speed

1.9 sec in total

First Response

410 ms

Resources Loaded

1.2 sec

Page Rendered

197 ms

books.coreknowledge.org screenshot

About Website

Click here to check amazing Books Core Knowledge content for United States. Otherwise, check out these important facts you probably never knew about books.coreknowledge.org

We are a nonprofit working for educational excellence and equity built on strong foundations of shared knowledge. Explore our approach and free resources.

Visit books.coreknowledge.org

Key Findings

We analyzed Books.coreknowledge.org page load time and found that the first response time was 410 ms and then it took 1.4 sec to load all DOM resources and completely render a web page. This is quite a good result, as only 25% of websites can load faster.

Performance Metrics

books.coreknowledge.org performance score

49

Measured Metrics

name

value

score

weighting

FCP (First Contentful Paint)

Value4.3 s

17/100

10%

LCP (Largest Contentful Paint)

Value6.5 s

9/100

25%

SI (Speed Index)

Value4.9 s

65/100

10%

TBT (Total Blocking Time)

Value500 ms

58/100

30%

CLS (Cumulative Layout Shift)

Value0

100/100

15%

TTI (Time to Interactive)

Value6.2 s

62/100

10%

Network Requests Diagram

home.php

410 ms

ga.js

28 ms

_1cde3deea69c0a6bee9ef1038916c52c.css

408 ms

_dc4a2deeb8568d81543a8b5d5da748a9.js

444 ms

__utm.gif

11 ms

Our browser made a total of 16 requests to load all elements on the main page. We found that 81% of them (13 requests) were addressed to the original Books.coreknowledge.org, 13% (2 requests) were made to Google-analytics.com and 6% (1 request) were made to Googletagmanager.com. The less responsive or slowest element that took the longest time to load (444 ms) belongs to the original domain Books.coreknowledge.org.

Page Optimization Overview & Recommendations

Page size can be reduced by 439.5 kB (61%)

Content Size

719.9 kB

After Optimization

280.3 kB

  • HTML
  • Images
  • JavaScript
  • CSS

In fact, the total size of Books.coreknowledge.org main page is 719.9 kB. This result falls beyond the top 1M of websites and identifies a large and not optimized web page that may take ages to load. 15% of websites need less resources to load. Javascripts take 381.0 kB which makes up the majority of the site volume.

HTML Optimization

-74%

Potential reduce by 12.6 kB

  • Original 17.1 kB
  • After minification 15.0 kB
  • After compression 4.5 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. This page needs HTML code to be minified as it can gain 2.1 kB, which is 12% 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 12.6 kB or 74% of the original size.

Image Optimization

-3%

Potential reduce by 4.6 kB

  • Original 146.5 kB
  • After minification 141.9 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. Books Core Knowledge images are well optimized though.

JavaScript Optimization

-71%

Potential reduce by 270.7 kB

  • Original 381.0 kB
  • After minification 332.2 kB
  • After compression 110.2 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 270.7 kB or 71% of the original size.

CSS Optimization

-86%

Potential reduce by 151.6 kB

  • Original 175.3 kB
  • After minification 135.0 kB
  • After compression 23.7 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. Books.coreknowledge.org needs all CSS files to be minified and compressed as it can save up to 151.6 kB or 86% of the original size.

Requests Breakdown

Number of requests can be reduced by 3 (20%)

Requests Now

15

After Optimization

12

  • Images
  • JavaScript
  • CSS

The browser has sent 15 CSS, Javascripts, AJAX and image requests in order to completely render the main page of Books Core Knowledge. We recommend that multiple CSS and JavaScript files should be merged into one by each type, as it can help reduce assets requests from 4 to 1 for JavaScripts and as a result speed up the page load time.

Network Requests Diagram

home.php

home.php

410 ms

ga.js

ga.js

28 ms

_1cde3deea69c0a6bee9ef1038916c52c.css

_1cde3deea69c0a6bee9ef1038916c52c.css

408 ms

_dc4a2deeb8568d81543a8b5d5da748a9.js

_dc4a2deeb8568d81543a8b5d5da748a9.js

444 ms

__utm.gif

__utm.gif

11 ms

_e768643ab556eb1c04e0a5e7bbe1ab76.js

_e768643ab556eb1c04e0a5e7bbe1ab76.js

74 ms

image.php

image.php

211 ms

image.php

image.php

151 ms

image.php

image.php

147 ms

spacer.gif

spacer.gif

82 ms

xlogo.gif

xlogo.gif

147 ms

payment_logos.png

payment_logos.png

112 ms

gtm.js

gtm.js

65 ms

hor_sprite.png

hor_sprite.png

238 ms

category_bullet.gif

category_bullet.gif

135 ms

header_bullet.gif

header_bullet.gif

169 ms

Accessibility Review

books.coreknowledge.org accessibility score

96

Accessibility Issues

Navigation

These are opportunities to improve keyboard navigation in your application.

Impact

Issue

High

Heading elements are not in a sequentially-descending order

Tables and lists

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

Impact

Issue

High

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

Best Practices

books.coreknowledge.org best practices score

92

Areas of Improvement

Trust and Safety

Impact

Issue

High

Does not use HTTPS

Low

Ensure CSP is effective against XSS attacks

General

Impact

Issue

Low

Detected JavaScript libraries

SEO Factors

books.coreknowledge.org 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

    EN

  • Language Claimed

    EN

  • Encoding

    UTF-8

Language claimed in HTML meta tag should match the language actually used on the web page. Otherwise Books.coreknowledge.org 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 Books.coreknowledge.org 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.

Social Sharing Optimization

books.coreknowledge.org

Open Graph description is not detected on the main page of Books Core Knowledge. 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: