Netherlands · Amsterdam Completed: Apr 4, 2026 18:21 UTCMobile 375 × 812
Desktop 1440 × 900
Score: 68 / 100
Based on 8 categories, 0 sections
The overall score is a weighted average of individual category scores. Categories with more impact on user experience and security carry more weight.
Weights reflect general web best practices. Individual needs may differ.
Content-Security-Policy header is missing
Cookie 'Homepage' is missing the Secure flag
Cookie 'bm_sz' is missing the Secure flag
Cookie 'homepage-new-exp' is missing the Secure flag
No Content-Security-Policy header found
[](https://beavercheck.com/results/3fe43e27-fd10-4799-9488-5dae2c729b44)<a href="https://beavercheck.com/results/3fe43e27-fd10-4799-9488-5dae2c729b44"><img src="https://beavercheck.com/badge?url=https%3A%2F%2Fwww.delta.com" alt="BeaverCheck Score"></a>https://beavercheck.com/badge?url=https%3A%2F%2Fwww.delta.comThis badge auto-updates with your latest scan result.
Thanks for your feedback!
Industry-standard audits powered by Google Lighthouse.
Key metrics that affect user experience.
First Contentful Paint First Contentful Paint — how long until the browser renders the first piece of content. Under 1.8s is good.
8.42 s
Largest Contentful Paint Largest Contentful Paint — how long until the largest visible element loads. Under 2.5s is good.
17.63 s
Total Blocking Time Total Blocking Time — total time the main thread was blocked, preventing user input. Under 200ms is good.
7.06 s
Cumulative Layout Shift Cumulative Layout Shift — measures visual stability. How much the page layout shifts during loading. Under 0.1 is good.
0.107
Speed Index Speed Index — how quickly content is visually displayed during load. Under 3.4s is good.
10.21 s
Time to Interactive Time to Interactive — how long until the page is fully interactive and responds to user input. Under 3.8s is good.
22.19 s
Audit breakdown by category with detailed findings.
Remove large, duplicate JavaScript modules from bundles to reduce unnecessary bytes consumed by network activity.
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
3rd party code can significantly impact load performance. Reduce and defer loading of 3rd party code to prioritize your page's content.
A long cache lifetime can speed up repeat visits to your page. Learn more about caching.
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.
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.
Each subpart has specific improvement strategies. Ideally, most of the LCP time should be spent on loading the resources, not within delays.
Optimize LCP by making the LCP image discoverable from the HTML immediately, and avoiding lazy-loading
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.
Reducing the download time of images can improve the perceived load time of the page and LCP. Learn more about optimizing image size
| URL | Resource Size | Est Savings | |
|---|---|---|---|
Ready For Adventure? section.w-full > div.image-card > div.card-image-ratio > img.card-image-content | www.delta.com/content/dam/delta-tnt/homepage/card-cd/brycecanyon-ut-slc-945.webp | 150.6 KiB | 105.4 KiB |
Discover Travel Products section.w-full > div.image-card > div.card-image-ratio > img.card-image-content | www.delta.com/content/dam/delta-tnt/homepage/btf/wf-3383622-01-1050x600.webp | 139.8 KiB | 99.1 KiB |
| /content/dam/delta-com/products/delta-experiences/main-ca... | 91.0 KiB | 47.4 KiB | |
| /content/dam/delta-com/products/delta-experiences/delta-p... | 59.8 KiB | 35.7 KiB | |
Image of the FlyDelta App div.w-full > div.image-card > div.card-image-ratio > img.card-image-content | www.delta.com/content/dam/delta-tnt/homepage/btf/wf-3175001-02-1050x600.webp | 56.0 KiB | 33.3 KiB |
Elevate Your Flight Experience section.w-full > div.image-card > div.card-image-ratio > img.card-image-content | /content/dam/delta-tnt/homepage/card-cd/premium-cabin-dea... | 72.5 KiB | 32.5 KiB |
How Can I Change/Cancel My Flight? div.w-full > div.image-card > div.card-image-ratio > img.card-image-content | www.delta.com/content/dam/delta-tnt/homepage/covid/icon-flight-changes-1000.webp | 8.7 KiB | 4.6 KiB |
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.
These insights are also available in the Chrome DevTools Performance Panel - record a trace to view more detailed information.
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.
Redirects introduce additional delays before the page can be loaded. Learn how to avoid page redirects.
| URL | Time Spent |
|---|---|
| www.delta.com/ | 12.3 s |
| www.delta.com/eu/en | 0.0 ms |
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
| Element | Layout shift score |
|---|---|
Book Your Next Trip
Explore our current flight deals
and plan your next adventu… body > idp-root > idp-content-body > div#content-body-mach-core | 0.037 |
Delta and our third party partners access and store data on your device as nece… body > div#onetrust-consent-sdk > div#onetrust-banner-sdk | 0.014 |
Delta and our third party partners access and store data on your device as nece… body > div#onetrust-consent-sdk > div#onetrust-banner-sdk | 0.007 |
How Can I Change/Cancel My Flight?
We understand that your plans may change. It… idp-content-body > div#content-body-mach-core > div.cmp-container > div.cards | 0.004 |
Delta and our third party partners access and store data on your device as nece… body > div#onetrust-consent-sdk > div#onetrust-banner-sdk | 0.004 |
Delta and our third party partners access and store data on your device as nece… body > div#onetrust-consent-sdk > div#onetrust-banner-sdk | 0.002 |
Delta and our third party partners access and store data on your device as nece… body > div#onetrust-consent-sdk > div#onetrust-banner-sdk | 0.002 |
Delta and our third party partners access and store data on your device as nece… body > div#onetrust-consent-sdk > div#onetrust-banner-sdk | 0.002 |
Delta and our third party partners access and store data on your device as nece… body > div#onetrust-consent-sdk > div#onetrust-banner-sdk | 0.001 |
Delta and our third party partners access and store data on your device as nece… body > div#onetrust-consent-sdk > div#onetrust-banner-sdk | 0.001 |
Delta and our third party partners access and store data on your device as nece… body > div#onetrust-consent-sdk > div#onetrust-banner-sdk | 0.001 |
Delta and our third party partners access and store data on your device as nece… body > div#onetrust-consent-sdk > div#onetrust-banner-sdk | 0.001 |
Delta and our third party partners access and store data on your device as nece… body > div#onetrust-consent-sdk > div#onetrust-banner-sdk | 0.001 |
Delta and our third party partners access and store data on your device as nece… body > div#onetrust-consent-sdk > div#onetrust-banner-sdk | 0.001 |
Delta and our third party partners access and store data on your device as nece… body > div#onetrust-consent-sdk > div#onetrust-banner-sdk | 0.001 |
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.
Reduce unused JavaScript and defer loading scripts until they are required to decrease bytes consumed by network activity. Learn how to reduce unused JavaScript.
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.
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
| Category | Time Spent |
|---|---|
| Script Evaluation | 15.3 s |
| Other | 4.0 s |
| Script Parsing & Compilation | 2.3 s |
| Style & Layout | 1.2 s |
| Rendering | 433 ms |
| Parse HTML & CSS | 377 ms |
| Garbage Collection | 315 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
| Failure reason | Failure type |
|---|---|
| The page has an unload handler in the main frame. | Actionable |
| The page has an unload handler in a sub frame. | Actionable |
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.
Large network payloads cost users real money and are highly correlated with long load times. Learn how to reduce payload sizes.
More information about the performance of your application. These numbers don't directly affect the Performance score.
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.
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.
| Failing Elements |
|---|
div.bg-surface-navigation > div.hph-message-content > span.hph-description > a div.bg-surface-navigation > div.hph-message-content > span.hph-description > a |
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.
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.
| Failing Elements |
|---|
Explore our current flight deals div.hph-message-content > span.hph-description > span.no-underline > a |
and plan your next adventure. div.hph-message-content > span.hph-description > span.no-underline > a |
These items highlight common accessibility best practices.
Visible text labels that do not match the accessible name can result in a confusing experience for screen reader users. Learn more about accessible names.
| Failing Elements |
|---|
AMS
Amsterdam, Netherlands idp-book-widget-search-modal-mach-core > div.airport-search-modal > div#one-way-route-picker > button#one-way-route-picker-origin-button |
To
Destination idp-book-widget-search-modal-mach-core > div.airport-search-modal > div#one-way-route-picker > button#one-way-route-picker-destination-button |
Netherlands - English div > idp-language-selector > div#mach-homepage-footer-language-selector-container > a#mach-homepage-footer-language-selector |
Deprecated APIs will eventually be removed from the browser. Learn more about deprecated APIs.
| Deprecation / Warning | Source |
|---|---|
| SharedStorage | |
| SharedStorage | |
| Unload event listeners are deprecated and will be removed. | www.delta.com/resources/df032bb95163120c0d0265eb98f27f913a30d77a1d98e line 141, col 127 |
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
| Source | Description |
|---|---|
A bad HTTP response code (444) was received when fetching the script. | |
A bad HTTP response code (444) was received when fetching the script. | |
Failed to load resource: the server responded with a status of 404 () | |
www.delta.com/eu/en line 37, col 0 | Refused to execute script from 'https://www.delta.com/akam/13/4addec96' because its MIME type ('text/html') is not executable, and strict MIME type checking is enabled. |
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.
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.
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
| Uncrawlable Link |
|---|
Select other Location and Language div.pop-up-box > div.pop-up-box-content > div.flex > a.link |
To appear in search results, crawlers need access to your app.
Canonical links suggest which URL to show in search results. Learn more about canonical links.
Format your HTML in a way that enables crawlers to better understand your app’s content.
Industry-standard audits powered by Google Lighthouse. — Desktop
Key metrics that affect user experience. — Desktop
First Contentful Paint First Contentful Paint — how long until the browser renders the first piece of content. Under 1.8s is good.
1.80 s
Largest Contentful Paint Largest Contentful Paint — how long until the largest visible element loads. Under 2.5s is good.
4.30 s
Total Blocking Time Total Blocking Time — total time the main thread was blocked, preventing user input. Under 200ms is good.
868 ms
Cumulative Layout Shift Cumulative Layout Shift — measures visual stability. How much the page layout shifts during loading. Under 0.1 is good.
0.040
Speed Index Speed Index — how quickly content is visually displayed during load. Under 3.4s is good.
3.32 s
Time to Interactive Time to Interactive — how long until the page is fully interactive and responds to user input. Under 3.8s is good.
5.06 s
Audit breakdown by category with detailed findings.
Remove large, duplicate JavaScript modules from bundles to reduce unnecessary bytes consumed by network activity.
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
3rd party code can significantly impact load performance. Reduce and defer loading of 3rd party code to prioritize your page's content.
A long cache lifetime can speed up repeat visits to your page. Learn more about caching.
Each subpart has specific improvement strategies. Ideally, most of the LCP time should be spent on loading the resources, not within delays.
Optimize LCP by making the LCP image discoverable from the HTML immediately, and avoiding lazy-loading
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.
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.
Reducing the download time of images can improve the perceived load time of the page and LCP. Learn more about optimizing image size
| URL | Resource Size | Est Savings | |
|---|---|---|---|
How Can I Change/Cancel My Flight? div.w-full > div.image-card > div.card-image-ratio > img.card-image-content | www.delta.com/content/dam/delta-tnt/homepage/covid/icon-flight-changes-1000.webp | 8.7 KiB | 5.3 KiB |
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.
| URL | Time Spent |
|---|---|
| www.delta.com/ | 2.5 s |
| www.delta.com/eu/en | 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.
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.
Reduce unused JavaScript and defer loading scripts until they are required to decrease bytes consumed by network activity. Learn how to reduce unused JavaScript.
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.
| URL | Total CPU Time | Script Evaluation | Script Parse |
|---|---|---|---|
| www.delta.com/homepage/26.3.8/mach-core/browser/polyfills.js | 1.2 s | 1.0 s | 1.9 ms |
| www.delta.com/resources/df032bb95163120c0d0265eb98f27f913a30d77a1d98e | 1.0 s | 896 ms | 33 ms |
| Unattributable | 843 ms | 194 ms | 0.0 ms |
| www.delta.com/NxvV2/ISv/V5F2/Si/veeSUD/1G7hbLaQkOX7LS/fQUZPAE/fnJiRG/IXEUIB | 448 ms | 383 ms | 45 ms |
| /NxvV2/ISv/V5F2/Si/veeSUD/wb7hbLaQ/K0ciPAE/UHQfJX/dcDxdt?... | 376 ms | 290 ms | 77 ms |
| www.delta.com/eu/en | 368 ms | 5.1 ms | 1.7 ms |
| tms.delta.com/delta/dl_anderson/Bootstrap.js | 346 ms | 274 ms | 54 ms |
| assets.adobedtm.com/3b29aa0834b1/0e49b4a4297a/launch-ab7c06f028a9.min.js | 237 ms | 172 ms | 55 ms |
| www.delta.com/homepage/26.3.8/mach-core/browser/main.js | 171 ms | 3.2 ms | 167 ms |
| cdn.cookielaw.org/scripttemplates/202503.1.0/otBannerSdk.js | 136 ms | 92 ms | 19 ms |
| www.delta.com/akam/13/4addec96 | 72 ms | 69 ms | 1.6 ms |
| www.delta.com/NxvV2/ISv/V5F2/Si/veeSUD/wb/d1V3OwE/UmB7Xj/cGAGcp | 55 ms | 40 ms | 9.9 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
| Category | Time Spent |
|---|---|
| Script Evaluation | 3.7 s |
| Other | 936 ms |
| Script Parsing & Compilation | 537 ms |
| Style & Layout | 262 ms |
| Parse HTML & CSS | 101 ms |
| Garbage Collection | 90 ms |
| Rendering | 66 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
| Failure reason | Failure type |
|---|---|
| The page has an unload handler in the main frame. | Actionable |
| The page has an unload handler in a sub frame. | Actionable |
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.
Large network payloads cost users real money and are highly correlated with long load times. Learn how to reduce payload sizes.
Set an explicit width and height on image elements to reduce layout shifts and improve CLS. Learn how to set image dimensions
| URL | |
|---|---|
Refundable Only Help Icon div.flex > div.flex > div.w-[24px] > img.grayscale-effect | /content/dam/delta-applications/sitewide/capability/fligh... |
More information about the performance of your application. These numbers don't directly affect the Performance score.
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.
Assistive technologies, like screen readers, can't interpret ARIA attributes with invalid values. Learn more about valid values for ARIA attributes.
| Failing Elements |
|---|
Book ul#mach-core-header-nav-primary-list > div.flex > li#mach-core-header-nav-primary-0 > a#headPrimary1 |
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.
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.
| Failing Elements |
|---|
div.bg-surface-navigation > div.hph-message-content > span.hph-description > a div.bg-surface-navigation > div.hph-message-content > span.hph-description > a |
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.
Visible text labels that do not match the accessible name can result in a confusing experience for screen reader users. Learn more about accessible names.
| Failing Elements |
|---|
AMS
Amsterdam, Netherlands idp-book-widget-search-modal-mach-core > div.airport-search-modal > div#one-way-route-picker > button#one-way-route-picker-origin-button |
To
Destination idp-book-widget-search-modal-mach-core > div.airport-search-modal > div#one-way-route-picker > button#one-way-route-picker-destination-button |
Depart - Return div.gap-8 > idp-date-picker-mach-core.laptop:w-[195.5px] > div.flex > button#date-picker-trigger-qf2ac54hdr8 |
Netherlands - English div > idp-language-selector > div#mach-homepage-footer-language-selector-container > a#mach-homepage-footer-language-selector |
Deprecated APIs will eventually be removed from the browser. Learn more about deprecated APIs.
| Deprecation / Warning | Source |
|---|---|
| SharedStorage | |
| Unload event listeners are deprecated and will be removed. | www.delta.com/resources/df032bb95163120c0d0265eb98f27f913a30d77a1d98e line 141, col 127 |
| SharedStorage | |
| Unload event listeners are deprecated and will be removed. | www.delta.com/resources/df032bb95163120c0d0265eb98f27f913a30d77a1d98e line 141, col 127 |
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
| Source | Description |
|---|---|
A bad HTTP response code (444) was received when fetching the script. | |
A bad HTTP response code (444) was received when fetching the script. | |
Failed to load resource: the server responded with a status of 404 () | |
www.delta.com/eu/en line 65, col 0 | Refused to execute script from 'https://www.delta.com/akam/13/4addec96' because its MIME type ('text/html') is not executable, and strict MIME type checking is enabled. |
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.
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.
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
| Uncrawlable Link |
|---|
Select other Location and Language div.pop-up-box > div.pop-up-box-content > div.flex > a.link |
To appear in search results, crawlers need access to your app.
Canonical links suggest which URL to show in search results. Learn more about canonical links.
Format your HTML in a way that enables crawlers to better understand your app’s content.
Send Feedback