Lighthouse Mobile
· 0 checks — Mobile Lighthouse audit -- Performance, Accessibility, Best Practices, and SEO category breakdown.Detailed Report
Audit breakdown by category with detailed findings.
Performance
Insights
Remove large, duplicate JavaScript modules from bundles to reduce unnecessary bytes consumed by network activity.
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
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.
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.
Performance issues directly impact user engagement and conversion rates.
| Request | Cache TTL | Transfer Size |
|---|---|---|
| /KAU4D/3/_I/zTpL/t1eXkK6H/3z5kcDJQuLr0Nhui/R05geBwNCA/c0V... | 21600.0 s | 180.8 KiB |
| /KAU4D/3/_I/zTpL/t1eXkK6H/Qr5kcDYruL/FRVseBwNCA/SwxNLR/oQ... | 21600.0 s | 156.3 KiB |
| app.usercentrics.eu/browser-ui/latest/loader.js | 3600.0 s | 10.8 KiB |
| mosaic02.ztat.net/rnd/ng/app-qr-code/app-qr.png | 0.0 ms | 7.7 KiB |
| www.zalando.es/akam/13/54f5f134 | 21600.0 s | 9.3 KiB |
| js-de.sentry-cdn.com/83b56e9b949f4d020211cbf6b3e542ad.min.js | 3600.0 s | 2.8 KiB |
| app.eu.usercentrics.eu/session/1px.png?settingsId=arL_G7jv7 | 1800.0 s | 1.2 KiB |
Your first network request is the most important. Reduce its latency by avoiding redirects, ensuring a fast server response, and enabling text compression.
Performance issues directly impact user engagement and conversion rates.
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.
Performance issues directly impact user engagement and conversion rates.
Reducing the download time of images can improve the perceived load time of the page and LCP. Learn more about optimizing image size
Performance issues directly impact user engagement and conversion rates.
| URL | Resource Size | Est Savings | |
|---|---|---|---|
Cuatro personas jugando a la petanca al aire libre, una mujer con pantalones co… div.JT3_zV > div.KVKCn3 > picture > img.mo6ZnF | /cnt/contentful-apps/uploads/66634e5f-6609-4db9-adcd-23c7... | 130.0 KiB | 109.3 KiB |
Mujer con blusa blanca y falda negra sentada en la acera junto a un hombre con … div.JT3_zV > div.KVKCn3 > picture > img.mo6ZnF | /cnt/contentful-apps/uploads/8011b707-8e25-4890-b1e9-dcd4... | 77.8 KiB | 59.4 KiB |
Optimize LCP by making the LCP image discoverable from the HTML immediately, and avoiding lazy-loading
Performance issues directly impact user engagement and conversion rates.
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.
Performance issues directly impact user engagement and conversion rates.
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.
Performance issues directly impact user engagement and conversion rates.
| URL | Transfer Size | Duration |
|---|---|---|
| js-de.sentry-cdn.com/83b56e9b949f4d020211cbf6b3e542ad.min.js | 2.8 KiB | 862 ms |
| mosaic02.ztat.net/zds/dx-ui/lib/atom-78.11.6.css | 33.2 KiB | 1.5 s |
| mosaic02.ztat.net/zds/tokens/tokens-lagom-stage-1-typography-3.13.24.css | 3.6 KiB | 808 ms |
| mosaic01.ztat.net/base-assets/9-1-0/assets/style.css | 3.1 KiB | 937 ms |
| mosaic01.ztat.net/base-assets/9-1-0/assets/z-shop-ui-styles.css | 8.6 KiB | 1.1 s |
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.
Performance issues directly impact user engagement and conversion rates.
| URL | Est Savings |
|---|---|
| mosaic01.ztat.net/zds/assets/fonts/76a99f7.woff2 | 20 ms |
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.
Performance issues directly impact user engagement and conversion rates.
| URL | Time Spent |
|---|---|
| zalando.com/ | 797 ms |
| www.zalando.es/ | 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.
Performance issues directly impact user engagement and conversion rates.
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.
Performance issues directly impact user engagement and conversion rates.
Diagnostics
Minifying CSS files can reduce network payload sizes. Learn how to minify CSS.
Performance issues directly impact user engagement and conversion rates.
| URL | Transfer Size | Est Savings |
|---|---|---|
| mosaic01.ztat.net/base-assets/9-1-0/assets/z-shop-ui-styles.css | 8.6 KiB | 3.4 KiB |
Minifying JavaScript files can reduce payload sizes and script parse time. Learn how to minify JavaScript.
Performance issues directly impact user engagement and conversion rates.
| URL | Transfer Size | Est Savings |
|---|---|---|
| mosaic01.ztat.net/base-assets/9-1-0/require-2.1.22.min.js | 7.9 KiB | 3.7 KiB |
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.
Performance issues directly impact user engagement and conversion rates.
| URL | Transfer Size | Est Savings |
|---|---|---|
| mosaic02.ztat.net/zds/dx-ui/lib/atom-78.11.6.css | 32.8 KiB | 29.0 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.
Performance issues directly impact user engagement and conversion rates.
| URL | Transfer Size | Est Savings |
|---|---|---|
| mosaic03.ztat.net/seo/glados/cbad27c6eaa5e42abf15-main.js | 225.4 KiB | 196.9 KiB |
| mosaic02.ztat.net/rnd/ng/re-common-chunk/index-252fdc6d1c203653e8bf.js | 172.9 KiB | 121.4 KiB |
| www.googletagmanager.com/gtm.js?id=GTM-T3W9FX&l=dataLayer | 150.5 KiB | 74.4 KiB |
| www.googletagmanager.com/gtag/js?id=AW-1006368194&cx=c>m=4e6550 | 143.8 KiB | 65.6 KiB |
| mosaic01.ztat.net/pnl/gtag/js?id=G-MDW1S9PQPW&l=dataLayerGA4 | 170.6 KiB | 62.3 KiB |
| app.usercentrics.eu/browser-ui/3.101.0/index.module.js | 120.6 KiB | 53.3 KiB |
| mosaic02.ztat.net/rnd/ng/runtime-concurrent-e8de382cfcdcc9a95fba.js | 157.9 KiB | 47.5 KiB |
| /KAU4D/3/_I/zTpL/t1eXkK6H/3z5kcDJQuLr0Nhui/R05geBwNCA/c0V... | 179.8 KiB | 39.2 KiB |
| /KAU4D/3/_I/zTpL/t1eXkK6H/Qr5kcDYruL/FRVseBwNCA/SwxNLR/oQ... | 156.1 KiB | 30.7 KiB |
| app.usercentrics.eu/browser-ui/3.101.0/VirtualServiceItem-ba2ffbd9.js | 48.7 KiB | 26.5 KiB |
| mosaic01.ztat.net/base-assets/9-1-0/assets/bundle.js | 79.8 KiB | 23.5 KiB |
| mosaic02.ztat.net/rnd/ng/header/index-5988b4452e5a672fb3e0.js | 35.3 KiB | 21.5 KiB |
Consider reducing the time spent parsing, compiling, and executing JS. You may find delivering smaller JS payloads helps with this. Learn how to reduce Javascript execution time.
Performance issues directly impact user engagement and conversion rates.
| URL | Total CPU Time | Script Evaluation | Script Parse |
|---|---|---|---|
| /KAU4D/3/_I/zTpL/t1eXkK6H/Qr5kcDYruL/FRVseBwNCA/SwxNLR/oQ... | 1.2 s | 1.1 s | 38 ms |
| mosaic01.ztat.net/base-assets/9-1-0/require-2.1.22.min.js | 1.0 s | 990 ms | 4.1 ms |
| Unattributable | 971 ms | 230 ms | 0.0 ms |
| mosaic01.ztat.net/base-assets/9-1-0/assets/bundle.js | 793 ms | 617 ms | 19 ms |
| /KAU4D/3/_I/zTpL/t1eXkK6H/3z5kcDJQuLr0Nhui/R05geBwNCA/c0V... | 653 ms | 492 ms | 41 ms |
| www.zalando.es/ | 435 ms | 31 ms | 59 ms |
| mosaic01.ztat.net/pnl/gtag/js?id=G-MDW1S9PQPW&l=dataLayerGA4 | 377 ms | 296 ms | 43 ms |
| www.googletagmanager.com/gtm.js?id=GTM-T3W9FX&l=dataLayer | 330 ms | 282 ms | 34 ms |
| app.usercentrics.eu/browser-ui/3.101.0/index.module.js | 288 ms | 210 ms | 1.4 ms |
| www.googletagmanager.com/gtag/js?id=AW-1006368194&cx=c>m=4e6550 | 145 ms | 107 ms | 37 ms |
| mosaic02.ztat.net/rnd/ng/runtime-concurrent-e8de382cfcdcc9a95fba.js | 96 ms | 44 ms | 48 ms |
| mosaic03.ztat.net/seo/glados/cbad27c6eaa5e42abf15-main.js | 93 ms | 0.8 ms | 92 ms |
| www.zalando.es/akam/13/54f5f134 | 88 ms | 80 ms | 5.1 ms |
| mosaic02.ztat.net/rnd/ng/re-common-chunk/index-252fdc6d1c203653e8bf.js | 87 ms | 25 ms | 46 ms |
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
Performance issues directly impact user engagement and conversion rates.
| Category | Time Spent |
|---|---|
| Script Evaluation | 4.8 s |
| Other | 937 ms |
| Script Parsing & Compilation | 528 ms |
| Style & Layout | 302 ms |
| Rendering | 150 ms |
| Garbage Collection | 137 ms |
| Parse HTML & CSS | 130 ms |
Many navigations are performed by going back to a previous page, or forwards again. The back/forward cache (bfcache) can speed up these return navigations. Learn more about the bfcache
Performance issues directly impact user engagement and conversion rates.
| Failure reason | Failure type |
|---|---|
| The page has an unload handler in the main frame. | Actionable |
| Pages with cache-control:no-store header cannot enter back/forward cache. | Actionable |
| Pages whose main resource has cache-control:no-store cannot enter back/forward cache. | Not actionable |
| Back/forward cache is disabled because some JavaScript network request received resource with Cache-Control: no-store header. | Not actionable |
Large network payloads cost users real money and are highly correlated with long load times. Learn how to reduce payload sizes.
Performance issues directly impact user engagement and conversion rates.
More information about the performance of your application. These numbers don't directly affect the Performance score.
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.
Performance issues directly impact user engagement and conversion rates.
| Failing Elements |
|---|
Asistente de Zalando div > div > div > div.uyF88V |
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.
Best Practices
General
Deprecated APIs will eventually be removed from the browser. Learn more about deprecated APIs.
Performance issues directly impact user engagement and conversion rates.
| Deprecation / Warning | Source |
|---|---|
| Unload event listeners are deprecated and will be removed. |
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
Performance issues directly impact user engagement and conversion rates.
| Source | Description |
|---|---|
Failed to load resource: the server responded with a status of 400 () |
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.
Performance issues directly impact user engagement and conversion rates.
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.
Crawling and Indexing
If your robots.txt file is malformed, crawlers may not be able to understand how you want your website to be crawled or indexed. Learn more about robots.txt.
Performance issues directly impact user engagement and conversion rates.
To appear in search results, crawlers need access to your app.