Tools & Wizards About Us
19ch.tv screenshot

Report Summary

  • 19

    Performance

    Renders faster than
    36% of other websites

  • 89

    Accessibility

    Visual factors better than
    that of 71% of websites

  • 92

    Best Practices

    More advanced features
    available than in
    80% of websites

  • 88

    SEO

    Google-friendlier than
    65% of websites

19ch.tv

葉一のYouTube授業と無料テキスト｜19ch（塾チャンネル）

Page Load Speed

3.2 sec in total

First Response

592 ms

Resources Loaded

2.1 sec

Page Rendered

482 ms

19ch.tv screenshot

About Website

Visit 19ch.tv now to see the best up-to-date 19 Ch content for Japan and also check out these interesting facts you probably never knew about 19ch.tv

葉一の公式サイト「19ch（塾チャンネル）」。2,000本以上のYouTube授業と専用プリントを無料公開中。とある男が授業をしてみた｜小学3年〜6年の算数、中学生の数学、国語、理科、社会、英語、高校数学に対応。高校受験の対策動画や、聞くだけで覚える暗記法も。

Visit 19ch.tv

Key Findings

We analyzed 19ch.tv page load time and found that the first response time was 592 ms and then it took 2.6 sec to load all DOM resources and completely render a web page. This is a poor result, as 50% of websites can load faster.

Performance Metrics

19ch.tv performance score

19

Measured Metrics

name

value

score

weighting

FCP (First Contentful Paint)

Value2.0 s

84/100

10%

LCP (Largest Contentful Paint)

Value4.9 s

29/100

25%

SI (Speed Index)

Value8.5 s

17/100

10%

TBT (Total Blocking Time)

Value4,820 ms

0/100

30%

CLS (Cumulative Layout Shift)

Value0.914

3/100

15%

TTI (Time to Interactive)

Value15.5 s

7/100

10%

Network Requests Diagram

19ch.tv

592 ms

top.css

197 ms

font-awesome.css

391 ms

responsive-min.css

393 ms

marketing.css

393 ms

Our browser made a total of 55 requests to load all elements on the main page. We found that 31% of them (17 requests) were addressed to the original 19ch.tv, 15% (8 requests) were made to Pagead2.googlesyndication.com and 13% (7 requests) were made to Googleads.g.doubleclick.net. The less responsive or slowest element that took the longest time to load (855 ms) belongs to the original domain 19ch.tv.

Page Optimization Overview & Recommendations

Page size can be reduced by 494.7 kB (33%)

Content Size

1.5 MB

After Optimization

1.0 MB

  • HTML
  • Images
  • JavaScript
  • CSS

In fact, the total size of 19ch.tv main page is 1.5 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. 60% of websites need less resources to load. Javascripts take 1.1 MB which makes up the majority of the site volume.

HTML Optimization

-80%

Potential reduce by 43.5 kB

  • Original 54.5 kB
  • After minification 46.9 kB
  • After compression 11.0 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 7.6 kB, which is 14% 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 43.5 kB or 80% of the original size.

Image Optimization

-23%

Potential reduce by 73.7 kB

  • Original 314.7 kB
  • After minification 241.0 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. Obviously, 19 Ch needs image optimization as it can save up to 73.7 kB or 23% of the original volume. The most popular and efficient tools for JPEG and PNG image optimization are Jpegoptim and PNG Crush.

JavaScript Optimization

-34%

Potential reduce by 370.4 kB

  • Original 1.1 MB
  • After minification 1.1 MB
  • After compression 728.6 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 370.4 kB or 34% of the original size.

CSS Optimization

-27%

Potential reduce by 7.1 kB

  • Original 26.9 kB
  • After minification 26.9 kB
  • After compression 19.7 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. 19ch.tv needs all CSS files to be minified and compressed as it can save up to 7.1 kB or 27% of the original size.

Requests Breakdown

Number of requests can be reduced by 26 (52%)

Requests Now

50

After Optimization

24

  • AJAX
  • Images
  • JavaScript
  • CSS

The browser has sent 50 CSS, Javascripts, AJAX and image requests in order to completely render the main page of 19 Ch. We recommend that multiple CSS and JavaScript files should be merged into one by each type, as it can help reduce assets requests from 21 to 1 for JavaScripts and from 7 to 1 for CSS and as a result speed up the page load time.

Network Requests Diagram

19ch.tv

19ch.tv

592 ms

top.css

top.css

197 ms

font-awesome.css

font-awesome.css

391 ms

responsive-min.css

responsive-min.css

393 ms

marketing.css

marketing.css

393 ms

js

js

54 ms

adsbygoogle.js

adsbygoogle.js

69 ms

cse.js

cse.js

48 ms

adsbygoogle.js

adsbygoogle.js

97 ms

google_custom_search_smwide.gif

google_custom_search_smwide.gif

84 ms

logo21.png

logo21.png

390 ms

lesson.png

lesson.png

391 ms

point.png

point.png

204 ms

9191.png

9191.png

391 ms

radio.png

radio.png

582 ms

request.png

request.png

585 ms

100mannin.png

100mannin.png

585 ms

consultation.png

consultation.png

585 ms

PCstudy.png

PCstudy.png

586 ms

desk.png

desk.png

855 ms

tv.png

tv.png

855 ms

show_ads_impl.js

show_ads_impl.js

92 ms

cse_element__ja.js

cse_element__ja.js

55 ms

default+ja.css

default+ja.css

76 ms

default.css

default.css

78 ms

google_custom_search_smwide.gif

google_custom_search_smwide.gif

70 ms

fontawesome-webfont.woff

fontawesome-webfont.woff

853 ms

zrt_lookup.html

zrt_lookup.html

81 ms

ads

ads

699 ms

ads

ads

373 ms

ads

ads

406 ms

async-ads.js

async-ads.js

60 ms

branding.png

branding.png

39 ms

clear.png

clear.png

11 ms

ads

ads

389 ms

error_handler.js

error_handler.js

35 ms

11633f1e916c91bbfa09ab1c92586fc3.js

11633f1e916c91bbfa09ab1c92586fc3.js

24 ms

load_preloaded_resource.js

load_preloaded_resource.js

60 ms

fa751b2aeb31bc20cb698a613f0fde71.js

fa751b2aeb31bc20cb698a613f0fde71.js

33 ms

abg_lite.js

abg_lite.js

71 ms

window_focus.js

window_focus.js

281 ms

qs_click_protection.js

qs_click_protection.js

70 ms

ufs_web_display.js

ufs_web_display.js

14 ms

b747694df2d2942986b42fb021d7b6f3.js

b747694df2d2942986b42fb021d7b6f3.js

69 ms

fa751b2aeb31bc20cb698a613f0fde71.js

fa751b2aeb31bc20cb698a613f0fde71.js

38 ms

icon.png

icon.png

26 ms

s

s

13 ms

css

css

80 ms

4Ua_rENHsxJlGDuGo1OIlJfC6l_24rlCK1Yo_Iqcsih3SAyH6cAwhX9RFD48TE63OOYKtrw2IJllpyw.ttf

4Ua_rENHsxJlGDuGo1OIlJfC6l_24rlCK1Yo_Iqcsih3SAyH6cAwhX9RFD48TE63OOYKtrw2IJllpyw.ttf

96 ms

4Ua_rENHsxJlGDuGo1OIlJfC6l_24rlCK1Yo_Iqcsih3SAyH6cAwhX9RFD48TE63OOYKtrwEIJllpyw.ttf

4Ua_rENHsxJlGDuGo1OIlJfC6l_24rlCK1Yo_Iqcsih3SAyH6cAwhX9RFD48TE63OOYKtrwEIJllpyw.ttf

113 ms

reactive_library.js

reactive_library.js

95 ms

ca-pub-4383688975914662

ca-pub-4383688975914662

138 ms

slotcar_library.js

slotcar_library.js

94 ms

activeview

activeview

74 ms

MnkYVOJ9Vxy1fW7IbW6uwlgEUewyXabIiklRFbW9srs.js

MnkYVOJ9Vxy1fW7IbW6uwlgEUewyXabIiklRFbW9srs.js

21 ms

Accessibility Review

19ch.tv accessibility score

89

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

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

19ch.tv 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

High

Page has valid source maps

SEO Factors

19ch.tv SEO score

88

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

High

Tap targets are not sized appropriately

Language and Encoding

  • Language Detected

    JA

  • Language Claimed

    JA

  • Encoding

    UTF-8

Language claimed in HTML meta tag should match the language actually used on the web page. Otherwise 19ch.tv can be misinterpreted by Google and other search engines. Our service has detected that Japanese is used on the page, and it matches the claimed language. Our system also found out that 19ch.tv 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

19ch.tv

Open Graph description is not detected on the main page of 19 Ch. 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: