Webpage: https://www.koso.co.jp
Device: Desktop Computer
Region: Japan (Tokyo)
Single Region Score
Consider lazy-loading offscreen and hidden images after all critical resources have finished loading to lower time to interactive. [Learn how to defer offscreen images].
Image formats like WebP and AVIF often provide better compression than PNG or JPEG, which means faster downloads and less data consumption. [Learn more about modern image formats].
Your first network request is the most important. Reduce its latency by avoiding redirects, ensuring a fast server response, and enabling text compression.
Errors logged to the console indicate unresolved problems. They can come from network request failures and other browser concerns. [Learn more about this errors in console diagnostic audit]
This is the largest contentful element painted within the viewport. [Learn more about the Largest Contentful Paint element]
Reduce unused JavaScript and defer loading scripts until they are required to decrease bytes consumed by network activity. [Learn how to reduce unused JavaScript].
Speed Index shows how quickly the contents of a page are visibly populated. [Learn more about the Speed Index metric].
Redirects introduce additional delays before the page can be loaded. [Learn how to avoid page redirects].
Layout shifts occur when elements move absent any user interaction. [Investigate the causes of layout shifts], such as elements being added, removed, or their fonts changing as the page loads.
Minifying CSS files can reduce network payload sizes. [Learn how to minify CSS].
Search engines may use `href` attributes on links to crawl websites. Ensure that the `href` attribute of anchor elements links to an appropriate destination, so more pages of the site can be discovered. [Learn how to make links crawlable]
Third party code can significantly impact load performance. [Reduce and defer loading of third party code] to prioritize your page's content.
Optimize LCP by making the LCP image [discoverable] from the HTML immediately, and [avoiding lazy-loading]
Link text (and alternate text for images, when used as links) that is discernible, unique, and focusable improves the navigation experience for screen reader users. [Learn how to make links accessible].
Low-contrast text is difficult or impossible for many users to read. [Learn how to provide sufficient color contrast].
Text-based resources should be served with compression (gzip, deflate or brotli) to minimize total network bytes. [Learn more about text compression].
Reduce unused rules from stylesheets and defer CSS not used for above-the-fold content to decrease bytes consumed by network activity. [Learn how to reduce unused CSS].
These are the largest layout shifts observed on the page. Each table item represents a single layout shift, and shows the element that shifted the most. Below each item are possible root causes that led to the layout shift. Some of these layout shifts may not be included in the CLS metric value due to [windowing]. [Learn how to improve CLS]