Analyze 21_21 DESIGN SIGHT

21_21 DESIGN SIGHT は、デザインを通して世界を見る場所です。 三宅一生、佐藤卓、深澤直人の3人のディレクターを中心とした、デザインのためのリサーチセンターであり、デザインについて考える場所であり、ものづくりの現場です。建築は安藤忠雄によるものです。

Page load speed analysis

  • 55/100

    Normal result
  • 6

    Successful tests
  • 2

    Failed tests
  • First response

    852 ms

  • Resources loaded

    3.7 sec

  • Page rendered

    184 ms

  • Total page load time

    4.8 sec

Visit now to see the best up-to-date 21 DESIGN SIGHT content for Japan and also check out these interesting facts you probably never knew about

We analyzed page load time and found that the first response time was 852 ms and then it took 3.9 sec to load all DOM resources and completely render a web page. This is a poor result, as 60% of websites can load faster.

Page optimization

  • HTML 13.8 kB
    Images 769.0 kB
    Javascripts 133.7 kB
    CSS 24.9 kB

    In fact, the total size of main page is 941.3 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. Images take 769.0 kB which makes up the majority of the site volume.

    • Original 13.8 kB
    • After minification 11.4 kB
    • After compression 3.2 kB

    HTML optimization

    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 2.4 kB, which is 17% 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 10.6 kB or 77% of the original size.

    • Original 769.0 kB
    • After optimization 750.8 kB

    Image optimization

    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. 21 DESIGN SIGHT images are well optimized though.

    • Original 133.7 kB
    • After minification 132.5 kB
    • After compression 47.2 kB

    JavaScript optimization

    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 86.5 kB or 65% of the original size.

    • Original 24.9 kB
    • After minification 19.3 kB
    • After compression 4.6 kB

    CSS optimization

    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. needs all CSS files to be minified and compressed as it can save up to 20.3 kB or 82% of the original size.

Network requests diagram

  • screen.css
  • colorbox2.css
  • jquery.js
  • jquery.cross-slide.min.js
  • swfobject.js
  • reset-min.css
  • fonts-min.css
  • bn_tour.jpg
  • bn_member.jpg
  • bn_recruit.jpg
  • bn_partner.jpg
  • bn_poster.jpg
  • lang_en.gif
  • background.gif
  • 21_21.gif
  • menu.gif
  • title_to_now.gif
  • ZK_poster.jpg
  • title_to_link.gif
  • bn_twitter.jpg
  • bn_facebook.jpg
  • bn_foundation.jpg
  • bn_tsukurukai.jpg
  • top_ad_books.jpg
  • bn_ZK_160326.jpg
  • bn_documents.gif
  • bn_miyakeissey_bg.jpg
  • title_to_news.gif
  • top_exhibition_topics_title.gif
  • top_2121_topics_title.gif
  • ga.js
  • __utm.gif
  • bn_miyakeissey_1
  • bn_miyakeissey_6
  • slide_ZK01.jpg
  • slide_ZK02.jpg
  • slide_ZK03.jpg
  • slide_ZK04.jpg
  • slide_ZK05.jpg
  • slide_ZK06.jpg

Our browser made a total of 42 requests to load all elements on the main page. We found that 95% of them (40 requests) were addressed to the original, 5% (2 requests) were made to The less responsive or slowest element that took the longest time to load (1.8 sec) belongs to the original domain

Additional info on


The browser has sent 41 CSS, Javascripts, AJAX and image requests in order to completely render the main page of 21 DESIGN SIGHT. We recommend that multiple CSS and JavaScript files should be merged into one by each type, as it can help reduce assets requests from 5 to 1 for JavaScripts and from 4 to 1 for CSS and as a result speed up the page load time.









Possible request optimization











Normal result

IP address uses IP address which is currently shared with 4 other domains. The more sites share the same IP address, the higher the host server’s workload is. It is strongly recommended that the host server should be changed or the hosting provider should be requested to give a different (separate) IP address for this domain.

Poor result

IP Trace

DNS records

Type Host Target/ip TTL Other
A 300
NS 300
NS 300
NS 300
NS 300

Language and encoding

Normal result


JA ja language flag


N/A  language flag





Language claimed in HTML meta tag should match the language actually used on the web page. Otherwise can be misinterpreted by Google and other search engines. Our service has detected that Japanese 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 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.

HTTPS certificate

SSL Certificate has no SSL certificate. Web browsing can be safer with HTTPS connection, so we suggest that it should be obtained for this site.

Normal result

Visitor World Map

Country of origin for 100% of all visits is Japan. It’s good for that their server is also located in Japan, as that enables the majority of their visitors to benefit from a much faster page load time.

Good result

Poor result

Social Sharing Optimization

Open Graph description is not detected on the main page of 21 DESIGN SIGHT. 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:

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