Skip to content
https://tuv.com

Lighthouse Desktop

· 0 checks — Desktop Lighthouse audit -- Performance, Accessibility, Best Practices, and SEO category breakdown.
SCORE
0
GRADE
FIX
0
REVIEW
0
PASS
0
INFO
0

Detailed Report

Audit breakdown by category with detailed findings.

67

Performance

Insights

Remove large, duplicate JavaScript modules from bundles to reduce unnecessary bytes consumed by network activity.

Why this matters

Performance issues directly impact user engagement and conversion rates.

Polyfills and transforms enable older browsers to use new JavaScript features. However, many aren't necessary for modern browsers. Consider modifying your JavaScript build process to not transpile Baseline features, unless you know you must support older browsers. Learn why most sites can deploy ES6+ code without transpiling

Why this matters

Performance issues directly impact user engagement and conversion rates.

3rd party code can significantly impact load performance. Reduce and defer loading of 3rd party code to prioritize your page's content.

Why this matters

Performance issues directly impact user engagement and conversion rates.

A long cache lifetime can speed up repeat visits to your page. Learn more about caching.

Why this matters

Performance issues directly impact user engagement and conversion rates.

RequestCache TTLTransfer Size
/content-media-files/taiwan/images/homepage-banner/landin...57326.0 s2.2 MiB
www.tuv.com/system-media-files/js/scripts.js35340.0 s507.8 KiB
/content-media-files/taiwan/images/homepage-banner/0916-u...155843.0 s841.0 KiB
/content-media-files/master-content/corporate-topics/sust...57757.0 s357.0 KiB
/content-media-files/taiwan/images/landing-page/sustainab...57326.0 s196.6 KiB
/content-media-files/master-content/corporate-topics/sust...108429.0 s244.8 KiB
/content-media-files/taiwan/images/homepage-banner/landin...105742.0 s236.4 KiB
/content-media-files/greater-china/images/20_13_p_goroden...105743.0 s229.4 KiB
www.tuv.com/content-media-files/taiwan/images/e-mark_core_8_3.jpg57326.0 s148.6 KiB
www.tuv.com/system-media-files/fonts/font-awesome/fontawesome-webfont.woff2772.0 s75.7 KiB
/content-media-files/taiwan/images/homepage-banner/0916-m...57327.0 s144.4 KiB
/system-media-files/fonts/font-awesome/fontawesome-webfon...1051.0 s75.7 KiB
www.tuv.com/system-media-files/css/style.css?2022091935332.0 s112.1 KiB
/content-media-files/master-content/services/products/022...43221.0 s115.4 KiB
/content-media-files/master-content/services/mobility/010...83013.0 s115.0 KiB
/content-media-files/master-content/services/mobility/104...83920.0 s111.3 KiB
/content-media-files/master-content/services/systems/0435...57327.0 s85.6 KiB
/content-media-files/taiwan/images/hot-topics/hot-topics_...155844.0 s121.2 KiB
/content-media-files/master-content/homepage/tuv-rheinlan...108642.0 s100.8 KiB
/content-media-files/master-content/services/products/101...142443.0 s112.2 KiB
/content-media-files/master-content/services/industrial-s...110098.0 s98.2 KiB
/content-media-files/master-content/global-landingpages/i...128925.0 s101.7 KiB
/content-media-files/master-content/services/mobility/010...45217.0 s67.6 KiB
/content-media-files/taiwan/images/hot-topics/hot_topics_...57327.0 s69.5 KiB
/content-media-files/master-content/services/products/020...113277.0 s87.5 KiB
/content-media-files/master-content/homepage/tuv-rheinlan...172615.0 s103.5 KiB
/content-media-files/taiwan/images/hot-topics/hot-topics_...108430.0 s79.3 KiB
/content-media-files/master-content/services/mobility/011...61413.0 s62.8 KiB
/content-media-files/master-content/services/academy-life...54619.0 s59.8 KiB
/content-media-files/master-content/services/industrial-s...142306.0 s82.6 KiB
/content-media-files/master-content/services/systems/0414...83261.0 s63.8 KiB
www.tuv.com/system-media-files/fonts/univers-lt/univers-lt-roman.woff21051.0 s27.2 KiB
/content-media-files/master-content/services/academy-life...123203.0 s61.8 KiB
/content-media-files/master-content/services/industrial-s...131633.0 s61.9 KiB
/content-media-files/master-content/services/industrial-s...125152.0 s58.4 KiB
/content-media-files/master-content/services/systems/0397...109274.0 s54.7 KiB
www.tuv.com/system-media-files/fonts/c5f91eda_7bd6_4dda_920e_a8aca7f11884.woff21372.0 s23.0 KiB
/content-media-files/master-content/homepage/tuv-rheinlan...118233.0 s52.8 KiB
www.tuv.com/system-media-files/fonts/roboto-v19-latin-italic.woff21552.0 s17.3 KiB
www.tuv.com/system-media-files/fonts/roboto-v19-latin-700.woff21051.0 s15.8 KiB
www.tuv.com/system-media-files/fonts/roboto-v19-latin-regular.woff2994.0 s15.7 KiB
/content-media-files/master-content/services/products/137...130492.0 s38.8 KiB
www.tuv.com/system-media-files/css/font-awesome/fontawesome.min.css166454.0 s7.3 KiB
www.tuv.com/system-media-files/css/flags-2.css32334.0 s1.3 KiB
/content-media-files/master-content/icons/tuv_r_icons_sem...2393.0 s867 B
www.tuv.com/content-media-files/master-content/icons/tuv_r_icons_project_rgb.svg3014.0 s859 B
/consentconfig/93626a84-94d4-4a5f-8a68-a23475d61c36/tuv.c...33896.0 s1.1 KiB
www.tuv.com/system-media-files/css/pti_booking.css164544.0 s1.3 KiB
www.tuv.com/system-media-files/js/empulse/emp-session-ajax.js88304.0 s865 B
www.tuv.com/system-media-files/js/pti_booking-min.js155513.0 s915 B
www.tuv.com/system-media-files/js/google-requirements/sha256_encoder.js136233.0 s756 B
www.tuv.com/system-media-files/js/pti_booking-min.js155513.0 s0 B
www.tuv.com/system-media-files/js/google-requirements/sha256_encoder.js136233.0 s0 B

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

Why this matters

Performance issues directly impact user engagement and conversion rates.

Consider setting font-display to swap or optional to ensure text is consistently visible. swap can be further optimized to mitigate layout shifts with font metric overrides.

Why this matters

Performance issues directly impact user engagement and conversion rates.

URLEst Savings
/system-media-files/fonts/font-awesome/fontawesome-webfon...40 ms

A forced reflow occurs when JavaScript queries geometric properties (such as offsetWidth) after styles have been invalidated by a change to the DOM state. This can result in poor performance. Learn more about forced reflows and possible mitigations.

Why this matters

Performance issues directly impact user engagement and conversion rates.

headings: [map[key:source label:Top function call valueType:source-location] map[granularity:1 key:reflowTime label:Total reflow time valueType:ms]]
items: [map[reflowTime:249.017 source:map[column:665616 line:1 type:source-location url:https://www.tuv.com/system-media-files/js/scripts.js urlProvider:network]]]
headings: [map[key:source label:Source valueType:source-location] map[granularity:1 key:reflowTime label:Total reflow time valueType:ms]]
items: [map[reflowTime:8.187 source:map[column:980710 line:0 type:source-location url:https://www.tuv.com/system-media-files/js/scripts.js urlProvider:network]] map[reflowTime:33.825 source:map[column:799082 line:0 type:source-location url:https://www.tuv.com/system-media-files/js/scripts.js urlProvider:network]] map[reflowTime:6.067 source:map[column:764910 line:0 type:source-location url:https://www.tuv.com/system-media-files/js/scripts.js urlProvider:network]] map[reflowTime:0.362 source:map[column:764993 line:0 type:source-location url:https://www.tuv.com/system-media-files/js/scripts.js urlProvider:network]] map[reflowTime:126.286 source:map[column:764319 line:0 type:source-location url:https://www.tuv.com/system-media-files/js/scripts.js urlProvider:network]] map[reflowTime:81.051 source:map[column:766371 line:0 type:source-location url:https://www.tuv.com/system-media-files/js/scripts.js urlProvider:network]] map[reflowTime:5.144 source:map[column:1.352397e+06 line:0 type:source-location url:https://www.tuv.com/system-media-files/js/scripts.js urlProvider:network]] map[reflowTime:35.012 source:map[column:798497 line:0 type:source-location url:https://www.tuv.com/system-media-files/js/scripts.js urlProvider:network]] map[reflowTime:117.804 source:map[column:797558 line:0 type:source-location url:https://www.tuv.com/system-media-files/js/scripts.js urlProvider:network]] map[reflowTime:36.119 source:map[column:764341 line:0 type:source-location url:https://www.tuv.com/system-media-files/js/scripts.js urlProvider:network]] map[reflowTime:0.42 source:map[column:802894 line:0 type:source-location url:https://www.tuv.com/system-media-files/js/scripts.js urlProvider:network]] map[reflowTime:0.316 source:map[column:400607 line:0 type:source-location url:https://www.tuv.com/system-media-files/js/scripts.js urlProvider:network]] map[reflowTime:9.731 source:map[column:662821 line:0 type:source-location url:https://www.tuv.com/system-media-files/js/scripts.js urlProvider:network]]]

Reducing the download time of images can improve the perceived load time of the page and LCP. Learn more about optimizing image size

Why this matters

Performance issues directly impact user engagement and conversion rates.

URLResource SizeEst Savings
div.tuv-teaser-container > div.component > a > img.lazyloaded div.tuv-teaser-container > div.component > a > img.lazyloaded
/content-media-files/master-content/homepage/tuv-rheinlan...103.1 KiB94.3 KiB
變壓器 div.tuv-teaser > a > div.tuv-teaser__image > img.lazyload
/content-media-files/master-content/services/products/022...115.0 KiB92.2 KiB
div.tuv-teaser-container > div.component > a > img.lazyloaded div.tuv-teaser-container > div.component > a > img.lazyloaded
/content-media-files/master-content/homepage/tuv-rheinlan...100.4 KiB91.8 KiB
車輛檢驗 div.tuv-teaser > a > div.tuv-teaser__image > img.ls-is-cached
/content-media-files/master-content/services/mobility/010...114.6 KiB91.7 KiB
中東驗證 div.tuv-teaser > a > div.tuv-teaser__image > img.lazyload
/content-media-files/master-content/services/products/101...111.9 KiB89.3 KiB
功能安全性 div.tuv-teaser > a > div.tuv-teaser__image > img.ls-is-cached
/content-media-files/master-content/services/mobility/104...110.9 KiB88.6 KiB
ISO 14001環境管理系統 div.tuv-teaser > a > div.tuv-teaser__image > img.lazyload
/content-media-files/master-content/global-landingpages/i...101.3 KiB80.9 KiB
歐洲壓力容器法規：PED、TPED、SPVD、AD 2000 div.tuv-teaser > a > div.tuv-teaser__image > img.lazyload
/content-media-files/master-content/services/industrial-s...97.9 KiB78.2 KiB
歐盟REACH法規 div.tuv-teaser > a > div.tuv-teaser__image > img.lazyload
/content-media-files/master-content/services/products/020...87.2 KiB69.6 KiB
FSC FM & COC div.tuv-teaser > a > div.tuv-teaser__image > img.lazyload
/content-media-files/master-content/services/systems/0435...85.2 KiB68.0 KiB
防爆認證 div.tuv-teaser > a > div.tuv-teaser__image > img.lazyload
/content-media-files/master-content/services/industrial-s...82.3 KiB65.7 KiB
div.tuv-teaser > a > div.tuv-teaser__image > img.lazyload div.tuv-teaser > a > div.tuv-teaser__image > img.lazyload
/content-media-files/taiwan/images/hot-topics/hot-topics_...120.8 KiB55.4 KiB
車輛評估和中古車管理 div.tuv-teaser > a > div.tuv-teaser__image > img.lazyload
/content-media-files/master-content/services/mobility/010...67.3 KiB53.7 KiB
ISO 9001 – TÜV Rheinland div.tuv-teaser > a > div.tuv-teaser__image > img.lazyload
/content-media-files/master-content/services/systems/0414...63.5 KiB50.7 KiB
評估服務 div.tuv-teaser > a > div.tuv-teaser__image > img.lazyload
/content-media-files/master-content/services/mobility/011...62.5 KiB49.9 KiB
金屬材料測試和分析 div.tuv-teaser > a > div.tuv-teaser__image > img.lazyload
/content-media-files/master-content/services/industrial-s...61.6 KiB49.2 KiB
驗證技能 – TÜV Rheinland div.tuv-teaser > a > div.tuv-teaser__image > img.lazyload
/content-media-files/master-content/services/academy-life...61.5 KiB49.1 KiB
div.tuv-teaser-container > div.component > a > img.lazyloaded div.tuv-teaser-container > div.component > a > img.lazyloaded
/content-media-files/master-content/homepage/tuv-rheinlan...52.5 KiB48.0 KiB
企業職業培訓 div.tuv-teaser > a > div.tuv-teaser__image > img.lazyload
/content-media-files/master-content/services/academy-life...59.4 KiB47.5 KiB
div.tuv-teaser > a > div.tuv-teaser__image > img.lazyload div.tuv-teaser > a > div.tuv-teaser__image > img.lazyload
/content-media-files/master-content/services/industrial-s...58.0 KiB46.3 KiB
BSCI 審核 div.tuv-teaser > a > div.tuv-teaser__image > img.lazyload
/content-media-files/master-content/services/systems/0397...54.4 KiB43.4 KiB
電線電纜 div.tuv-teaser > a > div.tuv-teaser__image > img.lazyload
/content-media-files/master-content/services/products/137...38.5 KiB30.7 KiB
div.tuv-slider__slide > div.tuv-slider__slide-container > a.tuv-slider__link > div.h-hidden-mobile div.tuv-slider__slide > div.tuv-slider__slide-container > a.tuv-slider__link > div.h-hidden-mobile
/content-media-files/master-content/corporate-topics/sust...244.4 KiB19.4 KiB
div.tuv-slider__slide > div.tuv-slider__slide-container > a.tuv-slider__link > div.h-hidden-mobile div.tuv-slider__slide > div.tuv-slider__slide-container > a.tuv-slider__link > div.h-hidden-mobile
/content-media-files/taiwan/images/homepage-banner/landin...236.0 KiB11.0 KiB

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

Why this matters

Performance issues directly impact user engagement and conversion rates.

lhId: page-24-DIV
nodeLabel: 香港機電工程署(EMSD)委任電動車工場認證機構
path: 1,HTML,1,BODY,7,DIV,1,DIV,0,DIV,0,DIV,0,DIV,0,DIV,0,DIV,0,A,0,DIV
selector: div.tuv-slider__slide > div.tuv-slider__slide-container > a.tuv-slider__link > div.h-hidden-mobile
snippet: <div class="h-hidden-mobile tuv-slider__bg-image" style="background-image: url(&quot;../../content-media-files/greater-china/images/20_13…&quot;);">

Avoid chaining critical requests by reducing the length of chains, reducing the download size of resources, or deferring the download of unnecessary resources to improve page load.

Why this matters

Performance issues directly impact user engagement and conversion rates.

description: [preconnect](https://developer.chrome.com/docs/lighthouse/performance/uses-rel-preconnect/) hints help the browser establish a connection earlier in the page load, saving time when the first request for that origin is made. The following are the origins that the page preconnected to.
title: Preconnected origins
value: no origins were preconnected
description: Add [preconnect](https://developer.chrome.com/docs/lighthouse/performance/uses-rel-preconnect/) hints to your most important origins, but try to use no more than 4.
title: Preconnect candidates

Requests are blocking the page's initial render, which may delay LCP. Deferring or inlining can move these network requests out of the critical path.

Why this matters

Performance issues directly impact user engagement and conversion rates.

URLTransfer SizeDuration
consent.cookiebot.eu/uc.js30.3 KiB531 ms
www.tuv.com/system-media-files/css/style.css?20220919112.1 KiB160 ms
www.tuv.com/system-media-files/css/pti_booking.css1.3 KiB
www.tuv.com/system-media-files/css/font-awesome/fontawesome.min.css7.3 KiB
www.tuv.com/system-media-files/css/flags-2.css1.3 KiB
www.tuv.com/system-media-files/css/additional_cn_style.css?202002270 B

These insights are also available in the Chrome DevTools Performance Panel - record a trace to view more detailed information.

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

Why this matters

Performance issues directly impact user engagement and conversion rates.

Estimated savings: 974 ms
URLTime Spent
tuv.com/711 ms
www.tuv.com/223 ms
www.tuv.com/greater-china/tw/40 ms
www.tuv.com/taiwan/tw/0.0 ms

Time to Interactive is the amount of time it takes for the page to become fully interactive. Learn more about the Time to Interactive metric.

Why this matters

Performance issues directly impact user engagement and conversion rates.

TTI

The maximum potential First Input Delay that your users could experience is the duration of the longest task. Learn more about the Maximum Potential First Input Delay metric.

Why this matters

Performance issues directly impact user engagement and conversion rates.

Diagnostics

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.

Why this matters

Performance issues directly impact user engagement and conversion rates.

Estimated savings: 120 ms 115.5 KiB
URLTransfer SizeEst Savings
www.tuv.com/system-media-files/css/style.css?20220919111.7 KiB104.7 KiB
13.5 KiB10.8 KiB

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

Why this matters

Performance issues directly impact user engagement and conversion rates.

Estimated savings: 280 ms 349.8 KiB
URLTransfer SizeEst Savings
www.tuv.com/system-media-files/js/scripts.js505.3 KiB349.8 KiB

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

Why this matters

Performance issues directly impact user engagement and conversion rates.

CategoryTime Spent
Script Evaluation713 ms
Style & Layout673 ms
Other264 ms
Parse HTML & CSS217 ms
Script Parsing & Compilation110 ms
Garbage Collection22 ms
Rendering19 ms

Large network payloads cost users real money and are highly correlated with long load times. Learn how to reduce payload sizes.

Why this matters

Performance issues directly impact user engagement and conversion rates.

URLTransfer Size
/content-media-files/taiwan/images/homepage-banner/landin...2.2 MiB
/content-media-files/taiwan/images/homepage-banner/0916-u...841.0 KiB
www.tuv.com/system-media-files/js/scripts.js507.8 KiB
/content-media-files/master-content/corporate-topics/sust...357.0 KiB
/content-media-files/master-content/corporate-topics/sust...244.8 KiB
/content-media-files/taiwan/images/homepage-banner/landin...236.4 KiB
/content-media-files/greater-china/images/20_13_p_goroden...229.4 KiB
/content-media-files/taiwan/images/landing-page/sustainab...196.6 KiB
www.tuv.com/content-media-files/taiwan/images/e-mark_core_8_3.jpg148.6 KiB
/content-media-files/taiwan/images/homepage-banner/0916-m...144.4 KiB

Set an explicit width and height on image elements to reduce layout shifts and improve CLS. Learn how to set image dimensions

Why this matters

Performance issues directly impact user engagement and conversion rates.

URL
div#8784085 > div.tuv-fullscreen-image > div.tuv-fullscreen-image__img-box > img.lazyloaded div#8784085 > div.tuv-fullscreen-image > div.tuv-fullscreen-image__img-box > img.lazyloaded
/content-media-files/master-content/corporate-topics/sust...

More information about the performance of your application. These numbers don't directly affect the Performance score.

●Layout shift culprits
●Optimize DOM size
●LCP breakdown
●Modern HTTP
●Optimize viewport for mobile
●Minify CSS
●Minify JavaScript
●JavaScript execution time 0.8 s
●Avoid long main-thread tasks 5 long tasks found
●Page didn't prevent back/forward cache restoration
●Network Requests
●Network Round Trip Times 160 ms
●Server Backend Latencies 290 ms
●Tasks
●Diagnostics
●Metrics
●Screenshot Thumbnails
●Final Screenshot
●Script Treemap Data
●Resources Summary
●Initial server response time was short Root document took 10 ms
○INP breakdown
○User Timing marks and measures
○Avoid non-composited animations
○Avoid large layout shifts
70

Accessibility

These checks highlight opportunities to improve the accessibility of your web app. Automatic detection can only detect a subset of issues and does not guarantee the accessibility of your web app, so manual testing is also encouraged.

ARIA

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.

Why this matters

Performance issues directly impact user engagement and conversion rates.

Failing Elements
div#main_content > div.tuv-slider > ul.slick-dots > li#slick-slide00 div#main_content > div.tuv-slider > ul.slick-dots > li#slick-slide00
div.break-in > div.tuv-teaser-container > ul.slick-dots > li#slick-slide10 div.break-in > div.tuv-teaser-container > ul.slick-dots > li#slick-slide10

Some ARIA parent roles must contain specific child roles to perform their intended accessibility functions. Learn more about roles and required children elements.

Why this matters

Performance issues directly impact user engagement and conversion rates.

Failing Elements
div.tuv-containers > div#main_content > div.tuv-slider > ul.slick-dots div.tuv-containers > div#main_content > div.tuv-slider > ul.slick-dots
div.break-out > div.break-in > div.tuv-teaser-container > ul.slick-dots div.break-out > div.break-in > div.tuv-teaser-container > ul.slick-dots

Assistive technologies, like screen readers, can't interpret ARIA attributes with invalid values. Learn more about valid values for ARIA attributes.

Why this matters

Performance issues directly impact user engagement and conversion rates.

Failing Elements
div#main_content > div.tuv-slider > ul.slick-dots > li#slick-slide00 div#main_content > div.tuv-slider > ul.slick-dots > li#slick-slide00
div.break-in > div.tuv-teaser-container > ul.slick-dots > li#slick-slide10 div.break-in > div.tuv-teaser-container > ul.slick-dots > li#slick-slide10

When an input field doesn't have an accessible name, screen readers announce it with a generic name, making it unusable for users who rely on screen readers. Learn more about input field labels.

Why this matters

Performance issues directly impact user engagement and conversion rates.

Failing Elements
香港機電工程署(EMSD)委任電動車工場認證機構 div#main_content > div.tuv-slider > div.slick-list > div.slick-track
主題 ANSI/ESD S20.20靜電放電防護管理系統 ESD靜電防護認證服務致力於確保您的產品在任何情況下都能保持最佳性能。 主題 化學測試服務 提… div.break-in > div.tuv-teaser-container > div.slick-list > div.slick-track

These are opportunities to improve the usage of ARIA in your application which may enhance the experience for users of assistive technology, like a screen reader.

Names and labels

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.

Why this matters

Performance issues directly impact user engagement and conversion rates.

Failing Elements
div.newsletter-box > form > div.tuv-input-group > button.tuv-btn div.newsletter-box > form > div.tuv-input-group > button.tuv-btn

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.

Why this matters

Performance issues directly impact user engagement and conversion rates.

Failing Elements
div.CybotCookiebotScrollContainer > div#CybotCookiebotDialogBodyContent > div#CybotCookiebotDialogBodyContentText > a div.CybotCookiebotScrollContainer > div#CybotCookiebotDialogBodyContent > div#CybotCookiebotDialogBodyContentText > a
div.header__inner > div.logo_wrapper > div.logo > a div.header__inner > div.logo_wrapper > div.logo > a
div.social-box > ul > li.component > a.tuv-social-share__link div.social-box > ul > li.component > a.tuv-social-share__link
div.social-box > ul > li.component > a.tuv-social-share__link div.social-box > ul > li.component > a.tuv-social-share__link
div.social-box > ul > li.component > a.tuv-social-share__link div.social-box > ul > li.component > a.tuv-social-share__link
div.social-box > ul > li.component > a.tuv-social-share__link div.social-box > ul > li.component > a.tuv-social-share__link
div.social-box > ul > li.component > a.tuv-social-share__link div.social-box > ul > li.component > a.tuv-social-share__link
div.social-box > ul > li.component > a.tuv-social-share__link div.social-box > ul > li.component > a.tuv-social-share__link
div.footer-top > div.footer-inner > div.back-top-box > a.back-top-btn div.footer-top > div.footer-inner > div.back-top-box > a.back-top-btn

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.

Contrast

Low-contrast text is difficult or impossible for many users to read. Learn how to provide sufficient color contrast.

Why this matters

Performance issues directly impact user engagement and conversion rates.

Failing Elements
主題 a > div.tuv-teaser__content > div.tuv-text > span.tuv-text--meta__title
主題 a > div.tuv-teaser__content > div.tuv-text > span.tuv-text--meta__title

These are opportunities to improve the legibility of your content.

Navigation

Properly ordered headings that do not skip levels convey the semantic structure of the page, making it easier to navigate and understand when using assistive technologies. Learn more about heading order.

Why this matters

Performance issues directly impact user engagement and conversion rates.

Failing Elements
德國萊因TÜV集團 div.component > a > div.tuv-teaser__content > h4.heading--v2

These are opportunities to improve keyboard navigation in your application.

Best practices

Disabling zooming is problematic for users with low vision who rely on screen magnification to properly see the contents of a web page. Learn more about the viewport meta tag.

Why this matters

Informational: a Permissions-Policy directive showing feature -> allowed origins.

Source: MDN Permissions-Policy

Failing Elements
head > meta head > meta

These items highlight common accessibility best practices.

○Interactive controls are keyboard focusable
○Interactive elements indicate their purpose and state
○The page has a logical tab order
○Visual order on the page follows DOM order
○User focus is not accidentally trapped in a region
○The user's focus is directed to new content added to the page
○HTML5 landmark elements are used to improve navigation
○Offscreen content is hidden from assistive technology
○Custom controls have associated labels
○Custom controls have ARIA roles
●`[aria-hidden="true"]` is not present on the document `<body>`
●`[role]`s have all required `[aria-*]` attributes
●`[role]`s are contained by their required parent element
●`[role]` values are valid
●`[aria-*]` attributes are valid and not misspelled
●Image elements have `[alt]` attributes
●Form elements have associated labels
●ARIA attributes are used as specified for the element's role
●Elements with `role="dialog"` or `role="alertdialog"` have accessible names.
●`[aria-hidden="true"]` elements do not contain focusable descendents
●Elements use only permitted ARIA attributes
●ARIA toggle fields have accessible names
●Document has a `<title>` element
●`<html>` element has a `[lang]` attribute
●`<html>` element has a valid value for its `[lang]` attribute
●Links are distinguishable without relying on color.
●Lists contain only `<li>` elements and script supporting elements (`<script>` and `<template>`).
●List items (`<li>`) are contained within `<ul>`, `<ol>` or `<menu>` parent elements
●No element has a `[tabindex]` value greater than 0
●Touch targets have sufficient size and spacing.
●`[lang]` attributes have a valid value
●Document has a main landmark.
●Deprecated ARIA roles were not used
●All heading elements contain content.
●Image elements do not have `[alt]` attributes that are redundant text.
○`[accesskey]` values are unique
○`button`, `link`, and `menuitem` elements have accessible names
○ARIA `meter` elements have accessible names
○ARIA `progressbar` elements have accessible names
○Elements with the `role=text` attribute do not have focusable descendents.
○ARIA `tooltip` elements have accessible names
○ARIA `treeitem` elements have accessible names
○The page contains a heading, skip link, or landmark region
○`<dl>`'s contain only properly-ordered `<dt>` and `<dd>` groups, `<script>`, `<template>` or `<div>` elements.
○Definition list items are wrapped in `<dl>` elements
○ARIA IDs are unique
○No form fields have multiple labels
○`<frame>` or `<iframe>` elements have a title
○`<html>` element has an `[xml:lang]` attribute with the same base language as the `[lang]` attribute.
○Input buttons have discernible text.
○`<input type="image">` elements have `[alt]` text
○The document does not use `<meta http-equiv="refresh">`
○`<object>` elements have alternate text
○Select elements have associated label elements.
○Skip links are focusable.
○Cells in a `<table>` element that use the `[headers]` attribute refer to table cells within the same table.
○`<th>` elements and elements with `[role="columnheader"/"rowheader"]` have data cells they describe.
○`<video>` elements contain a `<track>` element with `[kind="captions"]`
○Tables have different content in the summary attribute and `<caption>`.
○Uses ARIA roles only on compatible elements
○Identical links have the same purpose.
○Elements with visible text labels have matching accessible names.
○Tables use `<caption>` instead of cells with the `[colspan]` attribute to indicate a caption.
○`<td>` elements in a large `<table>` have one or more table headers.
96

Best Practices

General

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

Why this matters

Performance issues directly impact user engagement and conversion rates.

SourceDescription
www.tuv.com/system-media-files/css/additional_cn_style.css?20200227
Failed to load resource: the server responded with a status of 403 ()
www.tuv.com/taiwan/tw/tos-pti-locale-2023/rest/ajax/checkwebserviceavailable
Failed to load resource: the server responded with a status of 404 ()

Source maps translate minified code to the original source code. This helps developers debug in production. In addition, Lighthouse is able to provide further insights. Consider deploying source maps to take advantage of these benefits. Learn more about source maps.

Why this matters

Performance issues directly impact user engagement and conversion rates.

URL
www.tuv.com/system-media-files/js/scripts.js
●Uses HTTPS
●Avoids deprecated APIs
●Avoids third-party cookies
●Allows users to paste into input fields
●Avoids requesting the geolocation permission on page load
●Avoids requesting the notification permission on page load
●Displays images with correct aspect ratio
●Serves images with appropriate resolution
●Page has the HTML doctype
●Properly defines charset
●No issues in the `Issues` panel in Chrome Devtools
●Ensure CSP is effective against XSS attacks
●Use a strong HSTS policy
●Ensure proper origin isolation with COOP
●Mitigate DOM-based XSS with Trusted Types
●Detected JavaScript libraries
○Redirects HTTP traffic to HTTPS
○Mitigate clickjacking with XFO or CSP
92

SEO

These checks ensure that your page is following basic search engine optimization advice. There are many additional factors Lighthouse does not score here that may affect your search ranking, including performance on Core Web Vitals. Learn more about Google Search Essentials.

Content Best Practices

Meta descriptions may be included in search results to concisely summarize page content. Learn more about the meta description.

Why this matters

Performance issues directly impact user engagement and conversion rates.

Format your HTML in a way that enables crawlers to better understand your app’s content.

○Structured data is valid
●Page isn’t blocked from indexing
●Document has a `<title>` element
●Page has successful HTTP status code
●Links have descriptive text
●Links are crawlable
●robots.txt is valid
●Image elements have `[alt]` attributes
●Document has a valid `hreflang`
●Document has a valid `rel=canonical`

Send Feedback