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itmedia.co.jp Mobile Performance
18/100
These metrics represent real-world Chrome users experience viewing itmedia.co.jp on mobile devices. Reports are focused on loading performance and other critical factors that most affect user experience. Follow our guide to track, optimize, and improve the quality of your web pages.
User Loading Experience
Largest Contentful Paint
Cumulative Layout Shift
First Input Delay
First Contentful Paint
Metrics
Largest Contentful Paint2/100 8.3 s
Largest Contentful Paint marks the time at which the largest text or image is painted. Learn More
Time to Interactive5/100 17.0 s
Time to interactive is the amount of time it takes for the page to become fully interactive. Learn more.
Speed Index11/100 9.8 s
Speed Index shows how quickly the contents of a page are visibly populated. Learn more.
First Contentful Paint26/100 5.3 s
First Contentful Paint marks the time at which the first text or image is painted. Learn more.
Total Blocking Time28/100 840 ms
Sum of all time periods between FCP and Time to Interactive, when task length exceeded 50ms, expressed in milliseconds. Learn more.
Cumulative Layout Shift87/100 0.11
Cumulative Layout Shift measures the movement of visible elements within the viewport. Learn more.
Should Fix (19)
Opportunities
These suggestions can help your page load faster. They don't directly affect the Performance score.
Serve images in next-gen formats
Potential savings of 282 KiB
1,190 ms
Remove unused JavaScript
Potential savings of 232 KiB
1,170 ms
Efficiently encode images
Potential savings of 154 KiB
930 ms
Eliminate render-blocking resources
Potential savings of 670 ms
669 ms
Minify JavaScript
Potential savings of 8 KiB
120 ms
Enable text compression
Potential savings of 18 KiB
120 ms
Diagnostics
More information about the performance of your application. These numbers don't directly affect the Performance score.
Does not use passive listeners to improve scrolling performance
Avoid `document.write()`
Reduce the impact of third-party code
Third-party code blocked the main thread for 760 ms
Ensure text remains visible during webfont load
Serve static assets with an efficient cache policy
47 resources found
Minimize main-thread work
6.7 s
Reduce JavaScript execution time
3.6 s
Avoid chaining critical requests
37 chains found
User Timing marks and measures
8 user timings
Avoid long main-thread tasks
20 long tasks found
Avoid large layout shifts
4 elements found
Keep request counts low and transfer sizes small
171 requests • 1,561 KiB
Largest Contentful Paint element
1 element found
Passed Audits (11)
Remove unused CSS
Defer offscreen images
Minify CSS
Avoids enormous network payloads
Total size was 1,561 KiB
Avoids an excessive DOM size
371 elements
Preload key requests
Avoid multiple page redirects
Initial server response time was short
Root document took 100 ms
Properly size images
Potential savings of 29 KiB
Preconnect to required origins
Use video formats for animated content

itmedia.co.jp Mobile SEO
86/100
These checks ensure that your page is optimized for search engine results ranking. There are additional factors Lighthouse does not check that may affect your search ranking. Learn more. Run these additional validators on your site to check additional SEO best practices.
Should Fix (2)
Content Best Practices
Format your HTML in a way that enables crawlers to better understand your app’s content.
Document does not have a valid `rel=canonical`
Image elements do not have `[alt]` attributes
Passed Audits (12)
Has a `<meta name="viewport">` tag with `width` or `initial-scale`
Links are crawlable
Page isn’t blocked from indexing
Document has a valid `hreflang`
Tap targets are sized appropriately
100% appropriately sized tap targets
Document has a `<title>` element
Document has a meta description
Page has successful HTTP status code
Links have descriptive text
Document uses legible font sizes
69.61% legible text
robots.txt is valid
Document avoids plugins

itmedia.co.jp Mobile Best Practices
85/100
These checks highlight opportunities to improve the overall code health of itmedia.co.jp mobile page. Current recommendations will help to make your page fast and secure, to create a good user experience and to avoid deprecated technologies.
Should Fix (2)
Trust and Safety
Does not use HTTPS
2 insecure requests found
General
Browser errors were logged to the console
Passed Audits (12)
Links to cross-origin destinations are safe
Avoids Application Cache
Detected JavaScript libraries
Properly defines charset
Allows users to paste into password fields
Avoids front-end JavaScript libraries with known security vulnerabilities
Page has the HTML doctype
Avoids requesting the geolocation permission on page load
Avoids deprecated APIs
Serves images with appropriate resolution
Avoids requesting the notification permission on page load
Displays images with correct aspect ratio

itmedia.co.jp Mobile Progressive Web App
25/100
These checks validate the aspects of a Progressive Web App. Learn more. These checks are required by the baseline PWA Checklist but are not automatically checked by Lighthouse. They do not affect your score but it's important that you verify them manually.
Should Fix (9)
PWA Optimized
Does not set a theme color for the address bar.
Manifest doesn't have a maskable icon
Is not configured for a custom splash screen
Installable
Does not use HTTPS
2 insecure requests found
Does not register a service worker that controls page and `start_url`
Web app manifest does not meet the installability requirements
Fast and reliable
Current page does not respond with a 200 when offline
`start_url` does not respond with a 200 when offline
Page load is not fast enough on mobile networks
Interactive at 17.0 s
Passed Audits (5)
Has a `<meta name="viewport">` tag with `width` or `initial-scale`
Content is sized correctly for the viewport
Provides a valid `apple-touch-icon`
Redirects HTTP traffic to HTTPS
Contains some content when JavaScript is not available

itmedia.co.jp Mobile Accessibility
51/100
These checks highlight opportunities to improve the accessibility of your web app. Only a subset of accessibility issues can be automatically detected so manual testing is also encouraged. These items address areas which an automated testing tool cannot cover. Learn more in our guide on conducting an accessibility review.
Should Fix (4)
Best practices
These items highlight common accessibility best practices.
`[user-scalable="no"]` is used in the `<meta name="viewport">` element or the `[maximum-scale]` attribute is less than 5.
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.
`<frame>` or `<iframe>` elements do not have a title
Links do not have a discernible name
Image elements do not have `[alt]` attributes
Passed Audits (7)
`[aria-hidden="true"]` is not present on the document `<body>`
Heading elements appear in a sequentially-descending order
`<html>` element has a `[lang]` attribute
Document has a `<title>` element
Background and foreground colors have a sufficient contrast ratio
`<html>` element has a valid value for its `[lang]` attribute
The page contains a heading, skip link, or landmark region

Mobile Usability
99/100
These checks validate how easily a visitor can use itmedia.co.jp on a mobile device. Test results include a list of any mobile usability problems. Mobile usability problems are issues that can affect a user that visits the page on a mobile (small screen) device, including small font sizes (which are hard to read on a small screen).
Should Fix (1)
Size tap targets appropriately
Passed Audits (4)
Avoid plugins
Configure the viewport
Size content to viewport
Use legible font sizes

Mobile Speed
61/100
These checks analyze the performance of itmedia.co.jp on mobile devices and return PageSpeed score and information on how to improve the load time. What makes a good Progressive Web App?
Should Fix (7)
Eliminate render-blocking JavaScript and CSS in above-the-fold content
Optimize images
Leverage browser caching
Avoid landing page redirects
Enable compression
Minify JavaScript
Minify HTML
Passed Audits (3)
Reduce server response time
Minify CSS
Prioritize visible content
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