User Experience Performance Single Region Diagnostic Results

Webpage: https://www.ngk-insulators.com

Device: Desktop Computer

Region: United States East (Virginia)

Single Region Score

59
Page Performance Needs Improvement
A total of 24 improvements can achieve a higher score
Buttons do not have an accessible name

When a button doesn't have an accessible name, screen readers announce it as "button", making it unusable for users who rely on screen readers. [Learn how to make buttons more accessible].

Avoid an excessive DOM size

A large DOM will increase memory usage, cause longer [style calculations], and produce costly [layout reflows]. [Learn how to avoid an excessive DOM size].

Defer offscreen images

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].

Layout shift culprits

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.

Links are not crawlable

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]

Properly size images

Serve images that are appropriately-sized to save cellular data and improve load time. [Learn how to size images].

Efficiently encode images

Optimized images load faster and consume less cellular data. [Learn how to efficiently encode images].

Minify CSS

Minifying CSS files can reduce network payload sizes. [Learn how to minify CSS].

Largest Contentful Paint element

This is the largest contentful element painted within the viewport. [Learn more about the Largest Contentful Paint element]

Lists do not contain only `<li>` elements and script supporting elements (`<script>` and `<template>`).

Screen readers have a specific way of announcing lists. Ensuring proper list structure aids screen reader output. [Learn more about proper list structure].

Touch targets do not have sufficient size or spacing.

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].

`[aria-*]` attributes do not match their roles

Each ARIA `role` supports a specific subset of `aria-*` attributes. Mismatching these invalidates the `aria-*` attributes. [Learn how to match ARIA attributes to their roles].

List items (`<li>`) are not contained within `<ul>`, `<ol>` or `<menu>` parent elements.

Screen readers require list items (`

  • `) to be contained within a parent `
  • Reduce unused JavaScript

    Reduce unused JavaScript and defer loading scripts until they are required to decrease bytes consumed by network activity. [Learn how to reduce unused JavaScript].

    Reduce unused CSS

    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].

    LCP request discovery

    Optimize LCP by making the LCP image [discoverable] from the HTML immediately, and [avoiding lazy-loading]

    Third parties

    Third party code can significantly impact load performance. [Reduce and defer loading of third party code] to prioritize your page's content.

    Avoid large layout shifts

    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]

    Document request latency

    Your first network request is the most important. Reduce its latency by avoiding redirects, ensuring a fast server response, and enabling text compression.

    Avoid multiple page redirects

    Redirects introduce additional delays before the page can be loaded. [Learn how to avoid page redirects].

    Serve images in next-gen formats

    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].

    Eliminate render-blocking resources

    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].

    Links do not have descriptive text

    Descriptive link text helps search engines understand your content. [Learn how to make links more accessible].

    `[aria-*]` attributes are not valid or misspelled

    Assistive technologies, like screen readers, can't interpret ARIA attributes with invalid names. [Learn more about valid ARIA attributes].

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