Webpage: https://osg.co.jp
Device: Desktop Computer
Region: United States East (Virginia)
Single Region Score
Low-contrast text is difficult or impossible for many users to read. [Learn how to provide sufficient color contrast].
When definition lists are not properly marked up, screen readers may produce confusing or inaccurate output. [Learn how to structure definition lists correctly].
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]
Third party code can significantly impact load performance. [Reduce and defer loading of third party code] to prioritize your page's content.
Reduce unused JavaScript and defer loading scripts until they are required to decrease bytes consumed by network activity. [Learn how to reduce unused JavaScript].
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]
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]
Touch targets with sufficient size and spacing help users who may have difficulty targeting small controls to activate the targets. [Learn more about touch targets].
Screen reader users rely on frame titles to describe the contents of frames. [Learn more about frame titles].
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].
Informative elements should aim for short, descriptive alternative text. Alternative text that is exactly the same as the text adjacent to the link or image is potentially confusing for screen reader users, because the text will be read twice. [Learn more about the `alt` attribute].
Text-based resources should be served with compression (gzip, deflate or brotli) to minimize total network bytes. [Learn more about text compression].
Your first network request is the most important. Reduce its latency by avoiding redirects, ensuring a fast server response, and enabling text compression.
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].
This is the largest contentful element painted within the viewport. [Learn more about the Largest Contentful Paint element]
Resources are blocking the first paint of your page. Consider delivering critical JS/CSS inline and deferring all non-critical JS/styles. [Learn how to eliminate render-blocking resources].
Consider reducing the time spent parsing, compiling and executing JS. You may find delivering smaller JS payloads helps with this. [Learn how to minimize main-thread work]
Deprecated APIs will eventually be removed from the browser. [Learn more about deprecated APIs].
Optimize LCP by making the LCP image [discoverable] from the HTML immediately, and [avoiding lazy-loading]
Minifying CSS files can reduce network payload sizes. [Learn how to minify CSS].
Image display dimensions should match natural aspect ratio. [Learn more about image aspect ratio].
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].
Descriptive link text helps search engines understand your content. [Learn how to make links more accessible].
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 JavaScript files can reduce payload sizes and script parse time. [Learn how to minify JavaScript].