Report Summary

  • 51

    Performance

    Renders faster than
    69% of other websites

  • 85

    Accessibility

    Visual factors better than
    that of 58% of websites

  • 83

    Best Practices

    More advanced features
    available than in
    55% of websites

  • 93

    SEO

    Google-friendlier than
    83% of websites

sudoku.academy

Play sudoku online and for free on Sudoku Academy.

Page Load Speed

1.6 sec in total

First Response

45 ms

Resources Loaded

737 ms

Page Rendered

796 ms

sudoku.academy screenshot

About Website

Visit sudoku.academy now to see the best up-to-date Sudoku content and also check out these interesting facts you probably never knew about sudoku.academy

Whether you are a beginner or an advanced player, come and have fun solving sudoku puzzles online for free on Sudoku Academy. Earn points, see historical of all your games and a lot more.

Visit sudoku.academy

Key Findings

We analyzed Sudoku.academy page load time and found that the first response time was 45 ms and then it took 1.5 sec to load all DOM resources and completely render a web page. This is quite a good result, as only 30% of websites can load faster.

Performance Metrics

sudoku.academy performance score

51

Measured Metrics

name

value

score

weighting

FCP (First Contentful Paint)

Value2.1 s

80/100

10%

LCP (Largest Contentful Paint)

Value2.1 s

95/100

25%

SI (Speed Index)

Value6.7 s

36/100

10%

TBT (Total Blocking Time)

Value3,440 ms

2/100

30%

CLS (Cumulative Layout Shift)

Value0.059

98/100

15%

TTI (Time to Interactive)

Value16.7 s

5/100

10%

Network Requests Diagram

sudoku.academy

45 ms

www.sudoku.academy

111 ms

js

84 ms

amplitude-7.1.0-min.gz.js

37 ms

polyfill-7c70035a936d7adbea38.js

6 ms

Our browser made a total of 19 requests to load all elements on the main page. We found that 89% of them (17 requests) were addressed to the original Sudoku.academy, 5% (1 request) were made to Googletagmanager.com and 5% (1 request) were made to Cdn.amplitude.com. The less responsive or slowest element that took the longest time to load (372 ms) belongs to the original domain Sudoku.academy.

Page Optimization Overview & Recommendations

Page size can be reduced by 124.8 kB (69%)

Content Size

182.0 kB

After Optimization

57.2 kB

In fact, the total size of Sudoku.academy main page is 182.0 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. 25% of websites need less resources to load. HTML takes 151.8 kB which makes up the majority of the site volume.

HTML Optimization

-81%

Potential reduce by 123.6 kB

  • Original 151.8 kB
  • After minification 151.5 kB
  • After compression 28.1 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 123.6 kB or 81% of the original size.

Image Optimization

-10%

Potential reduce by 1.1 kB

  • Original 10.7 kB
  • After minification 9.6 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. Sudoku images are well optimized though.

JavaScript Optimization

-0%

Potential reduce by 0 B

  • Original 19.5 kB
  • After minification 19.5 kB
  • After compression 19.5 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. This website has mostly compressed JavaScripts.

Requests Breakdown

Number of requests can be reduced by 7 (41%)

Requests Now

17

After Optimization

10

The browser has sent 17 CSS, Javascripts, AJAX and image requests in order to completely render the main page of Sudoku. 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.

Accessibility Review

sudoku.academy accessibility score

85

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.

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

Best Practices

sudoku.academy best practices score

83

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

High

Browser errors were logged to the console

High

Page has valid source maps

SEO Factors

sudoku.academy SEO score

93

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

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 Sudoku.academy 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 Sudoku.academy 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

Open Graph data is detected on the main page of Sudoku. This is the best way to make the web page social media friendly. Here is how it looks like on Facebook: