Tools & Wizards About Us
cut-the-knot.org screenshot

Report Summary

  • 93

    Performance

    Renders faster than
    92% of other websites

  • 68

    Accessibility

    Visual factors better than
    that of 33% of websites

  • 58

    Best Practices

    More advanced features
    available than in
    20% of websites

  • 69

    SEO

    Google-friendlier than
    28% of websites

cut-the-knot.org

Interactive Mathematics Miscellany and Puzzles

Page Load Speed

1.9 sec in total

First Response

116 ms

Resources Loaded

1.6 sec

Page Rendered

211 ms

cut-the-knot.org screenshot

About Website

Welcome to cut-the-knot.org homepage info - get ready to check Cut The Knot best content for United States right away, or after learning these important things about cut-the-knot.org

An encyclopedic collection of math resources for all grades. Arithmetic games, problems, puzzles, and articles

Visit cut-the-knot.org

Key Findings

We analyzed Cut-the-knot.org page load time and found that the first response time was 116 ms and then it took 1.8 sec to load all DOM resources and completely render a web page. This is quite a good result, as only 40% of websites can load faster.

Performance Metrics

cut-the-knot.org performance score

93

Measured Metrics

name

value

score

weighting

FCP (First Contentful Paint)

Value2.3 s

75/100

10%

LCP (Largest Contentful Paint)

Value2.3 s

93/100

25%

SI (Speed Index)

Value4.4 s

74/100

10%

TBT (Total Blocking Time)

Value10 ms

100/100

30%

CLS (Cumulative Layout Shift)

Value0

100/100

15%

TTI (Time to Interactive)

Value2.4 s

99/100

10%

Network Requests Diagram

cut-the-knot.org

116 ms

cookie-consent.js

974 ms

walLoad.js

5 ms

bootstrap.min.css

11 ms

jquery.smartmenus.bootstrap.css

7 ms

Our browser made a total of 20 requests to load all elements on the main page. We found that 80% of them (16 requests) were addressed to the original Cut-the-knot.org, 5% (1 request) were made to Wolframcdn.com and 5% (1 request) were made to Code.jquery.com. The less responsive or slowest element that took the longest time to load (974 ms) relates to the external source Wolframcdn.com.

Page Optimization Overview & Recommendations

Page size can be reduced by 44.9 kB (21%)

Content Size

218.0 kB

After Optimization

173.1 kB

  • HTML
  • Images
  • JavaScript
  • CSS

In fact, the total size of Cut-the-knot.org main page is 218.0 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. 35% of websites need less resources to load. Images take 99.7 kB which makes up the majority of the site volume.

HTML Optimization

-80%

Potential reduce by 32.3 kB

  • Original 40.2 kB
  • After minification 34.0 kB
  • After compression 7.9 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 6.2 kB, which is 15% 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 32.3 kB or 80% of the original size.

Image Optimization

-2%

Potential reduce by 2.1 kB

  • Original 99.7 kB
  • After minification 97.6 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. Cut The Knot images are well optimized though.

JavaScript Optimization

-17%

Potential reduce by 10.2 kB

  • Original 60.5 kB
  • After minification 58.8 kB
  • After compression 50.4 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 10.2 kB or 17% of the original size.

CSS Optimization

-2%

Potential reduce by 376 B

  • Original 17.6 kB
  • After minification 17.6 kB
  • After compression 17.2 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. Cut-the-knot.org has all CSS files already compressed.

Requests Breakdown

Number of requests can be reduced by 7 (39%)

Requests Now

18

After Optimization

11

  • Images
  • JavaScript
  • CSS

The browser has sent 18 CSS, Javascripts, AJAX and image requests in order to completely render the main page of Cut The Knot. We recommend that multiple CSS and JavaScript files should be merged into one by each type, as it can help reduce assets requests from 8 to 1 for JavaScripts and as a result speed up the page load time.

Network Requests Diagram

cut-the-knot.org

cut-the-knot.org

116 ms

cookie-consent.js

cookie-consent.js

974 ms

walLoad.js

walLoad.js

5 ms

bootstrap.min.css

bootstrap.min.css

11 ms

jquery.smartmenus.bootstrap.css

jquery.smartmenus.bootstrap.css

7 ms

jquery-1.9.1.min.js

jquery-1.9.1.min.js

8 ms

jquery-2.1.0.min.js

jquery-2.1.0.min.js

14 ms

bootstrap.min.js

bootstrap.min.js

8 ms

jquery.smartmenus.js

jquery.smartmenus.js

7 ms

jquery.smartmenus.bootstrap.js

jquery.smartmenus.bootstrap.js

5 ms

cookie-consent.php

cookie-consent.php

349 ms

wal.js

wal.js

172 ms

ctklogo.png

ctklogo.png

31 ms

alex.jpg

alex.jpg

28 ms

CTKBook2020thumb.png

CTKBook2020thumb.png

27 ms

VerySmallFront.gif

VerySmallFront.gif

26 ms

SchoolZone.gif

SchoolZone.gif

39 ms

2003sm_web_awds.gif

2003sm_web_awds.gif

27 ms

MERLOT-classics-2004.gif

MERLOT-classics-2004.gif

38 ms

tbow_sh.gif

tbow_sh.gif

26 ms

Accessibility Review

cut-the-knot.org accessibility score

68

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.

Internationalization and localization

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

Impact

Issue

High

<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

High

Image elements do not have [alt] attributes

High

Links do not have a discernible name

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

cut-the-knot.org best practices score

58

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

User Experience

Impact

Issue

High

Serves images with low resolution

General

Impact

Issue

Low

Detected JavaScript libraries

SEO Factors

cut-the-knot.org SEO score

69

Search Engine Optimization Advices

Content Best Practices

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

Impact

Issue

High

Image elements do not have [alt] attributes

Language and Encoding

  • Language Detected

    EN

  • Language Claimed

    N/A

  • Encoding

    N/A

Language claimed in HTML meta tag should match the language actually used on the web page. Otherwise Cut-the-knot.org can be misinterpreted by Google and other search engines. Our service has detected that English 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 Cut-the-knot.org main page’s claimed encoding is . 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

cut-the-knot.org

Open Graph description is not detected on the main page of Cut The Knot. 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: