Spain · Madrid Completed: Apr 21, 2026 19:01 UTCMobile 375 × 812
Desktop 1440 × 900
Score: 70 / 100
Based on 8 categories, 0 sections
Room to improve — your 29.8s load time is above Google's 2.5s 'Good' threshold.
Several missing protections leave your users and data exposed.
Several issues make your site difficult for assistive technology users.
Well-optimized for search — your content is discoverable.
Good server performance with room for optimization.
Mostly compliant — a few items need attention.
Good content signals with minor gaps.
Heavier than average — reducing page weight saves energy and bandwidth.
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
Security gaps expose your site and users to attacks, eroding trust.
HSTS header is missing
Security gaps expose your site and users to attacks, eroding trust.
No Content-Security-Policy header found
Security gaps expose your site and users to attacks, eroding trust.
Page weighs 17.6 MB (4.6 MB transferred)
Performance issues directly impact user engagement and conversion rates.
2 control(s) without accessible label
Accessibility issues exclude users with disabilities — up to 15% of your potential audience.
High impact, low effort — start here.
High impact, requires investment.
Small gains, minimal effort.
Nothing in this quadrant — good news.
Low impact, high effort — do last.
Nothing in this quadrant — good news.
[](https://beavercheck.com/results/5fb42d3c-158b-434f-baf4-8ee241a1a9f6)<a href="https://beavercheck.com/results/5fb42d3c-158b-434f-baf4-8ee241a1a9f6"><img src="https://beavercheck.com/badge?url=https%3A%2F%2Fsi.edu" alt="BeaverCheck Score"></a>https://beavercheck.com/badge?url=https%3A%2F%2Fsi.eduThis badge auto-updates with your latest scan result.
Your site performs reasonably well, but a few targeted fixes could meaningfully improve results. Your LCP of 29.8s exceeds Google's 2.5s 'Good' threshold and the 1 performance issue below directly contributes to it. Addressing the critical issues below would have the most immediate impact on your user trust.
7 barrier(s) likely increasing bounce by ~32%.
Page takes 29.8s to load
+12% bounceUsers abandon at ~3s — you're 27.3s over the 2.5s threshold
Fix: Optimize render-blocking resources, preload the hero image, and compress images
Page feels frozen for 1.2s
+5% bounceClicks on the primary CTA are ignored while JavaScript runs
Fix: Break up long tasks; defer non-critical JavaScript to post-hydration
No HSTS header
+1% bounceReturning visitors are briefly exposed to downgrade attacks on first request
Fix: Set Strict-Transport-Security: max-age=31536000; includeSubDomains
No Content-Security-Policy header
+1% bounceHigher XSS blast radius — one compromised script can exfiltrate the checkout form
Fix: Ship a reporting-only CSP first, then enforce once violations are clean
2 form field(s) without a label
+4% bounceScreen readers skip unlabeled fields; autofill can't identify them; checkout abandonment spikes
Fix: Associate every input with a visible <label for="…">; add autocomplete attributes
No structured data
+2% bounceNo rich-result eligibility in Google — lower SERP CTR vs competitors with stars and prices
Fix: Add JSON-LD for your page type (Product, Article, FAQPage, LocalBusiness, …)
68 broken link(s) on the page
+5% bounceClicks land on 404s — trust drops and the session often ends
Fix: Fix or remove the broken destinations surfaced on the Content tab
Preliminary CRO audit — each barrier links to the tab with detailed analysis.
$500 investment → $1.16/month returns + USD 157,500 risk avoided
$500
5h · 5 findings
$1.16 /mo
~$14 / year
USD 157,500
if kept compliant
$150 — in quick wins — start here for the fastest payback
Figures combine localized regulatory fine ceilings, search/conversion value priced against local CPC, and bandwidth waste estimates. Results depend on implementation quality and audience composition. Not legal or financial advice.
5.0 developer hours at $100/hr
Based on United States rates ($100/hr)
Start here for the best return on investment
$13,126 / month at risk
~$157,514 / year if left unfixed
$157,500
+2 more
$1.16 /mo
14544.2 MB/mo × 0.080 USD/GB
Compliance figures represent the statutory maximum fine for the most severe triggered category, capped per regulation — not the sum of per-finding penalties. Based on published regulatory fine ranges. This is not legal advice.
Unique monthly visitors from your analytics
Purchases, signups, or key actions
Optional — for revenue estimation
more engaged visitors from reduced bounce
Fix 5 critical issues to capture this value
Based on Google/Deloitte research ("Milliseconds Make Millions") showing a ~7% bounce rate increase per additional second of LCP above the 2.5s "Good" threshold.
Your site's LCP: → estimated after fixes.
These are estimates based on industry research — actual results vary
Your data stays in your browser — nothing is sent to our servers
Thanks for your feedback!
We'll use a cached audit if available, or offer to scan.
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.
16.22 s
Largest Contentful Paint Largest Contentful Paint — how long until the largest visible element loads. Under 2.5s is good.
29.77 s
Total Blocking Time Total Blocking Time — total time the main thread was blocked, preventing user input. Under 200ms is good.
1.24 s
Cumulative Layout Shift Cumulative Layout Shift — measures visual stability. How much the page layout shifts during loading. Under 0.1 is good.
0.000
Speed Index Speed Index — how quickly content is visually displayed during load. Under 3.4s is good.
16.22 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.
30.11 s
Audit breakdown by category with detailed findings.
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
Shipping ES5 transpiled code to modern browsers wastes bytes — every user with an evergreen browser pays for compatibility you don't need.
Most users today run browsers that natively support ES6+, async/await, optional chaining, and the rest of modern JavaScript. Transpiling to ES5 'just in case' adds 20-40% to your bundle for no benefit. Configure your build to target a modern browserslist, or ship a differential bundle pair (modern + legacy) with the module/nomodule pattern.
Source: Google web.dev / Lighthouse
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.
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 | |
|---|---|---|---|
Castle with firerworks div.slide-content > figure.c-figure > picture > img | /sites/default/files/styles/full_width_mobile/public/page... | 64.9 KiB | 45.7 KiB |
Each subpart has specific improvement strategies. Ideally, most of the LCP time should be spent on loading the resources, not within delays.
Performance issues directly impact user engagement and conversion rates.
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.
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.
These insights are also available in the Chrome DevTools Performance Panel - record a trace to view more detailed information.
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.
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 |
|---|---|
| si.edu/ | 1.0 s |
| www.si.edu/ | 0.0 ms |
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.
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 |
|---|---|---|
| www.si.edu/core/misc/ajax.js?v=10.6.5 | 25.5 KiB | 17.9 KiB |
| www.si.edu/core/misc/jquery.form.js?v=4.3.0 | 18.2 KiB | 8.4 KiB |
| www.si.edu/core/misc/drupal.js?v=10.6.5 | 8.8 KiB | 6.9 KiB |
| www.si.edu/core/misc/drupal.js?v=10.6.5 | 8.8 KiB | 6.9 KiB |
| www.si.edu/core/misc/drupal.js?v=10.6.5 | 8.8 KiB | 6.9 KiB |
| www.si.edu/core/misc/message.js?v=10.6.5 | 3.3 KiB | 2.2 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.
Multi-megabyte JavaScript bundles delay every interactive feature on the page.
This is the Lighthouse audit fired when too much JS is shipped relative to what executes. The fix isn't a config flag — it requires bundle analysis (webpack-bundle-analyzer, rollup-plugin-visualizer), splitting routes into chunks, lazy-loading off-screen components, and removing unused dependencies. Fundamentally different from minification: minifying reduces byte count, this reduces what's downloaded at all.
Source: Google web.dev / Lighthouse
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.
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 | 5.0 s |
| Other | 1.3 s |
| Script Parsing & Compilation | 974 ms |
| Style & Layout | 490 ms |
| Garbage Collection | 149 ms |
| Parse HTML & CSS | 118 ms |
| Rendering | 81 ms |
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 |
|---|---|---|
| /sites/default/files/css/css_5xhAlRvn6wV5JITQK6SeFSwZ-en7... | 23.5 KiB | 18.9 KiB |
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.
Set an explicit width and height on image elements to reduce layout shifts and improve CLS. Learn how to set image dimensions
Performance issues directly impact user engagement and conversion rates.
| URL | |
|---|---|
Home footer.region > div.c-site-footer__inner > a.site-footer__logo > img.logo__image | www.si.edu/themes/custom/si_basetheme_drupal/images/logo-secondary-white.svg |
Home div.c-site-header__lower > div.c-site-branding > a#block-siedu-sitebranding > img.logo__image | www.si.edu/sites/default/themes/siedu/logo.svg |
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.
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.
Performance issues directly impact user engagement and conversion rates.
| Failing Elements |
|---|
div.c-site-header__lower > divy.c-site-header__lower-inner > div#c-menu > button#nav-trigger div.c-site-header__lower > divy.c-site-header__lower-inner > div#c-menu > button#nav-trigger |
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.
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 |
|---|---|
| SharedStorage | |
| StorageType.persistent is deprecated. Please use standardized navigator.storage instead. | |
| Fledge | |
| AttributionReporting | connect.facebook.net/en_US/fbevents.js line 279, col 769 |
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 403 () | |
Refused to execute script from 'https://www.si.edu/TSPD/?type=18' because its MIME type ('text/html') is not executable, and strict MIME type checking is enabled. |
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.
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.
1.29 s
Largest Contentful Paint Largest Contentful Paint — how long until the largest visible element loads. Under 2.5s is good.
4.73 s
Total Blocking Time Total Blocking Time — total time the main thread was blocked, preventing user input. Under 200ms is good.
60 ms
Cumulative Layout Shift Cumulative Layout Shift — measures visual stability. How much the page layout shifts during loading. Under 0.1 is good.
0.015
Speed Index Speed Index — how quickly content is visually displayed during load. Under 3.4s is good.
3.42 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.
6.60 s
Audit breakdown by category with detailed findings.
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
Shipping ES5 transpiled code to modern browsers wastes bytes — every user with an evergreen browser pays for compatibility you don't need.
Most users today run browsers that natively support ES6+, async/await, optional chaining, and the rest of modern JavaScript. Transpiling to ES5 'just in case' adds 20-40% to your bundle for no benefit. Configure your build to target a modern browserslist, or ship a differential bundle pair (modern + legacy) with the module/nomodule pattern.
Source: Google web.dev / Lighthouse
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.
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.
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.
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 | |
|---|---|---|---|
Harmony in Blue and Gold The Peacock Room section.c-link-card > div.c-link-card__wrap > figure.c-link-card__figure > img | /sites/default/files/styles/grid/public/teaser/fs-f1904.6... | 108.6 KiB | 98.2 KiB |
Duke Ellington section.c-link-card > div.c-link-card__wrap > figure.c-link-card__figure > img | /sites/default/files/styles/grid/public/teaser/duke-ellin... | 74.9 KiB | 65.0 KiB |
3D scan of interior of Apollo command module div.paragraph--74427 > section.c-navigation-card > figure.c-navigation-card__figure > img | /sites/default/files/styles/grid/public/teaser/3d-360-apo... | 84.9 KiB | 62.7 KiB |
spring landscape section.c-link-card > div.c-link-card__wrap > figure.c-link-card__figure > img | /sites/default/files/styles/grid/public/teaser/saam-1968.... | 71.7 KiB | 62.2 KiB |
A white carousel horse amidst other colored horses. section.c-link-card > div.c-link-card__wrap > figure.c-figure > img | /sites/default/files/styles/grid/public/carousel_restored... | 71.6 KiB | 62.1 KiB |
Two large bison stand in a field of yellow wildflowers. div.paragraph--74426 > section.c-navigation-card > figure.c-navigation-card__figure > img | /sites/default/files/styles/grid/public/bison_photo.jpeg.... | 82.4 KiB | 60.2 KiB |
Triple-image Ella Fitzgerald section.c-link-card > div.c-link-card__wrap > figure.c-link-card__figure > img | /sites/default/files/styles/grid/public/slideshow/archivc... | 67.8 KiB | 58.8 KiB |
magazine cover section.c-link-card > div.c-link-card__wrap > figure.c-link-card__figure > img | /sites/default/files/styles/grid/public/se-mag-307_1.png.... | 60.6 KiB | 52.6 KiB |
Smithsonian Castle in spring with bright pink tulips section.c-callout-card > div.c-callout-card__wrap > figure.c-figure > img | /sites/default/files/styles/grid/public/Spring_SI_Castle.... | 62.5 KiB | 47.8 KiB |
t-rex fossil section.c-link-card > div.c-link-card__wrap > figure.c-link-card__figure > img | /sites/default/files/styles/grid/public/newsdesk/kits/nhb... | 48.4 KiB | 42.0 KiB |
The Asian elephant calf born Feb. 2, 2026, explores her habitat in the Elephant… section.c-link-card > div.c-link-card__wrap > figure.c-link-card__figure > img | /sites/default/files/styles/grid/public/NZCBI_linh_mai.jp... | 40.3 KiB | 34.9 KiB |
The entire image is awash in intricate clouds, and swathes of superheated gas. section.c-link-card > div.c-link-card__wrap > figure.c-link-card__figure > img | /sites/default/files/styles/grid/public/teaser/30dorb_lg1... | 40.1 KiB | 34.7 KiB |
An American bison standing and looking at the camera. section.c-link-card > div.c-link-card__wrap > figure.c-figure > img | /sites/default/files/styles/grid/public/blog/bison-010.jp... | 39.9 KiB | 34.6 KiB |
Illustration of a skeleton hand holding a sparkling blue diamond. section.c-link-card > div.c-link-card__wrap > figure.c-link-card__figure > img | /sites/default/files/styles/grid/public/page_banner/sd_s0... | 38.1 KiB | 33.0 KiB |
Elephant with Cher section.c-link-card > div.c-link-card__wrap > figure.c-link-card__figure > img | /sites/default/files/styles/grid/public/se-circles300elep... | 36.6 KiB | 31.7 KiB |
Earth from Space section.c-link-card > div.c-link-card__wrap > figure.c-link-card__figure > img | /sites/default/files/styles/grid/public/teaser/earth-day-... | 36.3 KiB | 31.5 KiB |
NASA's Space Launch System on the launch pad. section.c-link-card > div.c-link-card__wrap > figure.c-link-card__figure > img | /sites/default/files/styles/grid/public/nasm-slc.jpg.webp... | 36.0 KiB | 31.2 KiB |
Upper Antelope Canyon in Arizona section.c-link-card > div.c-link-card__wrap > figure.c-link-card__figure > img | /sites/default/files/styles/grid/public/journey-circle.pn... | 31.6 KiB | 27.4 KiB |
An illustration of a group of muppets next to the Smithsonian castle. section.c-link-card > div.c-link-card__wrap > figure.c-link-card__figure > img | /sites/default/files/styles/grid/public/sidedoor/s10e01-w... | 30.9 KiB | 26.8 KiB |
Illustration of Kali Holder with purple hair surrounded by profiles of animals. section.c-link-card > div.c-link-card__wrap > figure.c-link-card__figure > img | /sites/default/files/styles/grid/public/s11e18-web_small.... | 30.2 KiB | 26.2 KiB |
Three children in a wicker baby carriage with an American flag. div.paragraph--74425 > section.c-navigation-card > figure.c-navigation-card__figure > img | /sites/default/files/styles/grid/public/children-carriage... | 41.7 KiB | 24.4 KiB |
T-shirts, mugs and other merchandise related to the Artemis moon mission. section.c-link-card > div.c-link-card__wrap > figure.c-link-card__figure > img | /sites/default/files/styles/grid/public/se-circles300-art... | 27.6 KiB | 23.9 KiB |
Illustration featuring a monkey face looking over trees and people with podcast… section.c-link-card > div.c-link-card__wrap > figure.c-link-card__figure > img | /sites/default/files/styles/grid/public/sidedoor/s10e15-w... | 21.9 KiB | 19.0 KiB |
A woman looks out a bay window, riveted by something beyond the pictorial space. div.paragraph--74424 > section.c-navigation-card > figure.c-navigation-card__figure > img | /sites/default/files/styles/grid/public/SAAM-1986.6.92_3.... | 31.8 KiB | 18.5 KiB |
A historic red brick building with turrets and flags surrounded by colorful tul… div.screen > div.container > div.lightbox > img.image | ucarecdn.com/39c61b4d-bc68-4126-ab59-6d21ed4e823f/-/resize/480x/-/format/auto/ | 39.0 KiB | 18.0 KiB |
lavender heeled ankle boots with Prince's Love Symbol as the zipper pull. section.c-link-card > div.c-link-card__wrap > figure.c-link-card__figure > img | /sites/default/files/styles/grid/public/NMAAHC-2020_27_2a... | 18.7 KiB | 16.2 KiB |
Castle with firerworks div.slide-content > figure.c-figure > picture > img | /sites/default/files/styles/hero_default/public/page_bann... | 114.6 KiB | 4.6 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.
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 |
|---|---|
| si.edu/ | 486 ms |
| www.si.edu/ | 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.
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 |
|---|---|---|
| www.si.edu/core/misc/ajax.js?v=10.6.5 | 25.5 KiB | 17.9 KiB |
| www.si.edu/core/misc/jquery.form.js?v=4.3.0 | 18.2 KiB | 8.4 KiB |
| www.si.edu/core/misc/drupal.js?v=10.6.5 | 8.8 KiB | 6.9 KiB |
| www.si.edu/core/misc/drupal.js?v=10.6.5 | 8.8 KiB | 6.9 KiB |
| www.si.edu/core/misc/drupal.js?v=10.6.5 | 8.8 KiB | 6.9 KiB |
| www.si.edu/core/misc/message.js?v=10.6.5 | 3.3 KiB | 2.2 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.
Multi-megabyte JavaScript bundles delay every interactive feature on the page.
This is the Lighthouse audit fired when too much JS is shipped relative to what executes. The fix isn't a config flag — it requires bundle analysis (webpack-bundle-analyzer, rollup-plugin-visualizer), splitting routes into chunks, lazy-loading off-screen components, and removing unused dependencies. Fundamentally different from minification: minifying reduces byte count, this reduces what's downloaded at all.
Source: Google web.dev / Lighthouse
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 | 1.3 s |
| Other | 464 ms |
| Script Parsing & Compilation | 265 ms |
| Style & Layout | 203 ms |
| Rendering | 56 ms |
| Parse HTML & CSS | 38 ms |
| Garbage Collection | 32 ms |
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 |
|---|---|---|
| /sites/default/files/css/css_5xhAlRvn6wV5JITQK6SeFSwZ-en7... | 23.5 KiB | 16.1 KiB |
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.
Set an explicit width and height on image elements to reduce layout shifts and improve CLS. Learn how to set image dimensions
Performance issues directly impact user engagement and conversion rates.
| URL | |
|---|---|
Home footer.region > div.c-site-footer__inner > a.site-footer__logo > img.logo__image | www.si.edu/themes/custom/si_basetheme_drupal/images/logo-secondary-white.svg |
Home div.c-site-header__lower > div.c-site-branding > a#block-siedu-sitebranding > img.logo__image | www.si.edu/sites/default/themes/siedu/logo.svg |
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.
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 |
|---|---|
| SharedStorage | |
| StorageType.persistent is deprecated. Please use standardized navigator.storage instead. | |
| Fledge | |
| AttributionReporting | connect.facebook.net/en_US/fbevents.js line 279, col 769 |
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 |
|---|---|
Refused to execute script from 'https://www.si.edu/' because its MIME type ('text/html') is not executable, and strict MIME type checking is enabled. |
Issues logged to the `Issues` panel in Chrome Devtools indicate unresolved problems. They can come from network request failures, insufficient security controls, and other browser concerns. Open up the Issues panel in Chrome DevTools for more details on each issue.
Performance issues directly impact user engagement and conversion rates.
| Issue type |
|---|
| Content security policy |
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.
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