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· 0 checks — Desktop Lighthouse audit -- Performance, Accessibility, Best Practices, and SEO category breakdown.
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Detailed Report

Audit breakdown by category with detailed findings.

66

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
/sites/default/files/styles/hero_default/public/page_bann...0.0 ms115.2 KiB
/sites/default/files/styles/grid/public/teaser/fs-f1904.6...0.0 ms109.1 KiB
/sites/default/files/styles/hero_default/public/26NES_SI-...0.0 ms97.4 KiB
/sites/default/files/styles/grid/public/teaser/3d-360-apo...0.0 ms85.4 KiB
connect.facebook.net/en_US/fbevents.js1200.0 s96.6 KiB
/sites/default/files/styles/grid/public/bison_photo.jpeg....0.0 ms82.9 KiB
/sites/default/files/styles/grid/public/teaser/duke-ellin...0.0 ms75.5 KiB
/sites/default/files/styles/hero_default/public/slideshow...0.0 ms74.9 KiB
/sites/default/files/styles/hero_default/public/slideshow...0.0 ms73.2 KiB
/sites/default/files/styles/grid/public/teaser/saam-1968....0.0 ms72.2 KiB
/sites/default/files/styles/grid/public/carousel_restored...0.0 ms72.2 KiB
/sites/default/files/styles/grid/public/slideshow/archivc...0.0 ms68.3 KiB
cdn.fundraiseup.com/widget/AVCYLAJJ0.0 ms65.2 KiB
/sites/default/files/styles/grid/public/Spring_SI_Castle....0.0 ms63.7 KiB
/sites/default/files/styles/hero_default/public/page_bann...0.0 ms61.5 KiB
/sites/default/files/styles/grid/public/se-mag-307_1.png....0.0 ms61.1 KiB
/sites/default/files/styles/grid/public/newsdesk/kits/nhb...0.0 ms48.6 KiB
/sites/default/files/styles/grid/public/children-carriage...0.0 ms41.9 KiB
/signals/config/203131454135018?v=2.9.303&r=stable&domain...1200.0 s46.1 KiB
/sites/default/files/styles/grid/public/NZCBI_linh_mai.jp...0.0 ms40.5 KiB
/sites/default/files/styles/grid/public/teaser/30dorb_lg1...0.0 ms40.3 KiB
/sites/default/files/styles/grid/public/blog/bison-010.jp...0.0 ms40.2 KiB
/sites/default/files/styles/grid/public/page_banner/sd_s0...0.0 ms38.4 KiB
/sites/default/files/styles/grid/public/se-circles300elep...0.0 ms36.8 KiB
/sites/default/files/styles/grid/public/teaser/earth-day-...0.0 ms36.5 KiB
/sites/default/files/styles/grid/public/nasm-slc.jpg.webp...0.0 ms36.3 KiB
/sites/default/files/styles/grid/public/SAAM-1986.6.92_3....0.0 ms32.0 KiB
/sites/default/files/styles/grid/public/journey-circle.pn...0.0 ms31.9 KiB
/sites/default/files/styles/grid/public/sidedoor/s10e01-w...0.0 ms31.1 KiB
/sites/default/files/styles/grid/public/s11e18-web_small....0.0 ms30.5 KiB
/sites/default/files/styles/grid/public/se-circles300-art...0.0 ms27.9 KiB
/sites/default/files/styles/grid/public/sidedoor/s10e15-w...0.0 ms22.2 KiB
/sites/default/files/styles/grid/public/NMAAHC-2020_27_2a...0.0 ms19.0 KiB
ucm-us.verint-cdn.com/files/sites/smithsonian/live/sdk.js86400.0 s42.1 KiB
scripts.clarity.ms/0.8.59/clarity.js86400.0 s26.2 KiB
www.si.edu/cdn-cgi/challenge-platform/h/b/scripts/jsd/0b8fb825cb67/main.js?14400.0 s12.8 KiB
cdn.fundraiseup.com/embed-data/elements-global/AVCYLAJJ.js0.0 ms8.1 KiB
cdn.fundraiseup.com/embed-data/elements-global/AVCYLAJJ.js0.0 ms8.0 KiB
/beacon.min.js/v8c78df7c7c0f484497ecbca7046644da177152312...86400.0 s10.7 KiB
/dcsuft0skadzpxvkk977nydg5_3r1t/dcs.gif?dcsredirect=1&dcs...0.0 ms982 B
cdn.fundraiseup.com/widget/AVCYLAJJ0.0 ms669 B
ucm-us.verint-cdn.com/files/sites/smithsonian/live/custom-style.css86400.0 s1.4 KiB
ucm-us.verint-cdn.com/files/sites/smithsonian/live/customcode.js86400.0 s1.0 KiB
cdn.jsdelivr.net/npm/micromodal/dist/micromodal.min.js604800.0 s2.6 KiB
/p.css?s=1&k=zop5pdr&ht=tk&f=36118.36119.36134.36135.4882...604800.0 s172 B
/tr/?id=203131454135018&ev=PageView&dl=https%3A%2F%2Fwww....0.0 ms16 B
www.si.edu/3600.0 s0 B
/beacon.min.js/v8c78df7c7c0f484497ecbca7046644da177152312...86400.0 s0 B
/beacon.min.js/v8c78df7c7c0f484497ecbca7046644da177152312...86400.0 s0 B
www.si.edu/cdn-cgi/challenge-platform/scripts/jsd/main.js14400.0 s0 B
/p.css?s=1&k=zop5pdr&ht=tk&f=36118.36119.36134.36135.4882...604800.0 s0 B
/p.css?s=1&k=zop5pdr&ht=tk&f=36118.36119.36134.36135.4882...604800.0 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
/af/2c8795/00000000000000007735eebd/30/l?primer=f592e0a4b...70 ms
/af/9e7dcb/00000000000000007735eebb/30/l?primer=f592e0a4b...50 ms
/af/92f8dc/00000000000000007735eeb6/30/l?primer=f592e0a4b...40 ms
/af/4ba8a2/0000000000000000773594a0/30/l?primer=7cdcb44be...35 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:22.409 source:map[column:22 line:19 type:source-location url:https://www.si.edu/core/misc/drupal.init.js?v=10.6.5 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:27.294 source:map[type:text value:[unattributed]]] map[reflowTime:0.353 source:map[column:33734 line:9 type:source-location url:https://cdn.jsdelivr.net/npm/gsap@3.12.5/dist/ScrollTrigger.min.js urlProvider:network]] map[reflowTime:11.655 source:map[column:13363 line:9 type:source-location url:https://cdn.jsdelivr.net/npm/gsap@3.12.5/dist/ScrollTrigger.min.js urlProvider:network]] map[reflowTime:0.869 source:map[column:16743 line:9 type:source-location url:https://cdn.jsdelivr.net/npm/gsap@3.12.5/dist/ScrollTrigger.min.js urlProvider:network]] map[reflowTime:19.061 source:map[column:55073 line:9 type:source-location url:https://cdn.jsdelivr.net/npm/gsap@3.12.5/dist/gsap.min.js urlProvider:network]] map[reflowTime:4.217 source:map[column:2269 line:7 type:source-location url:https://cdn.jsdelivr.net/npm/@splidejs/splide@4.1.4/dist/js/splide.min.js urlProvider:network]] map[reflowTime:1.225 source:map[column:372 line:0 type:source-location url:https://www.si.edu/themes/custom/si_basetheme_drupal/components/04-regions/site-header/site-header.js?v=5.x urlProvider:network]] map[reflowTime:0.146 source:map[column:3496 line:9 type:source-location url:https://cdn.jsdelivr.net/npm/gsap@3.12.5/dist/ScrollTrigger.min.js urlProvider:network]] map[reflowTime:0.426 source:map[column:9918 line:9 type:source-location url:https://cdn.jsdelivr.net/npm/gsap@3.12.5/dist/ScrollTrigger.min.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
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 KiB98.2 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 KiB65.0 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 KiB62.7 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 KiB62.2 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 KiB62.1 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 KiB60.2 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 KiB58.8 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 KiB52.6 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 KiB47.8 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 KiB42.0 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 KiB34.9 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 KiB34.7 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 KiB34.6 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 KiB33.0 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 KiB31.7 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 KiB31.5 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 KiB31.2 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 KiB27.4 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 KiB26.8 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 KiB26.2 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 KiB24.4 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 KiB23.9 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 KiB19.0 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 KiB18.5 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 KiB18.0 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 KiB16.2 KiB
Castle with firerworks div.slide-content > figure.c-figure > picture > img
/sites/default/files/styles/hero_default/public/page_bann...114.6 KiB4.6 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-25-IMG
nodeLabel: Castle with firerworks
path: 1,HTML,1,BODY,4,DIV,0,DIV,2,DIV,0,DIV,0,DIV,1,SECTION,1,DIV,0,UL,0,LI,0,DIV,0,FIGURE,0,PICTURE,6,IMG
selector: div.slide-content > figure.c-figure > picture > img
snippet: <img loading="lazy" width="645" height="430" src="https://www.si.edu/sites/default/files/styles/hero_default/public/page_ban…" alt="Castle with firerworks">

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
www.si.edu/modules/contrib/google_tag/js/gtm.js?tdbwpg982 B260 ms
www.si.edu/modules/contrib/google_tag/js/gtag.js?tdbwpg1.1 KiB260 ms
use.typekit.net/zop5pdr.css1.2 KiB
/sites/default/files/css/css_JX6OyIRI_N_w5XA8DOKjp0P4Y5ox...10.6 KiB322 ms
www.si.edu/core/misc/drupalSettingsLoader.js?v=10.6.5652 B
/sites/default/files/css/css_5xhAlRvn6wV5JITQK6SeFSwZ-en7...23.8 KiB383 ms
/p.css?s=1&k=zop5pdr&ht=tk&f=36118.36119.36134.36135.4882...172 B204 ms
/sites/default/files/css/css_IsKshnoQhYGhE41_pz3sMFTx7f8y...2.9 KiB137 ms
/sites/default/files/css/css_CJuaLk81J7BPx_uOslrk4KbAY7jm...425 B260 ms
www.si.edu/0 B
cdn.jsdelivr.net/npm/@splidejs/splide@4.1.4/dist/css/splide.min.css1.7 KiB230 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.

Why this matters

Performance issues directly impact user engagement and conversion rates.

Estimated savings: 486 ms
URLTime 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.

Why this matters

Performance issues directly impact user engagement and conversion rates.

TTI

Diagnostics

Minifying JavaScript files can reduce payload sizes and script parse time. Learn how to minify JavaScript.

Why this matters

Performance issues directly impact user engagement and conversion rates.

Estimated savings: 30 ms 49.3 KiB
URLTransfer SizeEst Savings
www.si.edu/core/misc/ajax.js?v=10.6.525.5 KiB17.9 KiB
www.si.edu/core/misc/jquery.form.js?v=4.3.018.2 KiB8.4 KiB
www.si.edu/core/misc/drupal.js?v=10.6.58.8 KiB6.9 KiB
www.si.edu/core/misc/drupal.js?v=10.6.58.8 KiB6.9 KiB
www.si.edu/core/misc/drupal.js?v=10.6.58.8 KiB6.9 KiB
www.si.edu/core/misc/message.js?v=10.6.53.3 KiB2.2 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.

Why this matters

Performance issues directly impact user engagement and conversion rates.

Estimated savings: 160 ms 1.7 MiB
URLTransfer SizeEst Savings
static.fundraiseup.com/checkout.9e2624d0be733d7f.js410.1 KiB365.9 KiB
static.fundraiseup.com/checkout.9e2624d0be733d7f.js410.1 KiB365.9 KiB
www.gstatic.com/recaptcha/releases/gTpTIWhbKpxADzTzkcabhXN4/recaptcha__en.js361.8 KiB176.9 KiB
static.fundraiseup.com/checkout-sentry-vendor.dda4c7629502a974.js111.7 KiB111.6 KiB
static.fundraiseup.com/checkout-sentry-vendor.dda4c7629502a974.js111.7 KiB111.6 KiB
static.fundraiseup.com/checkout-vendors.78ab7844d94042df.js105.2 KiB87.3 KiB
static.fundraiseup.com/checkout-vendors.78ab7844d94042df.js105.2 KiB87.3 KiB
www.googletagmanager.com/gtag/js?id=AW-971586094&cx=c&gtm=4e64h1144.6 KiB62.3 KiB
www.googletagmanager.com/gtag/js?id=G-ENWSWPLJYD&cx=c&gtm=4e64h1146.6 KiB61.5 KiB
www.googletagmanager.com/gtag/js?id=AW-16464893431&cx=c&gtm=4e64h1143.6 KiB61.2 KiB
www.googletagmanager.com/gtm.js?id=GTM-TT2JWKJ171.0 KiB60.0 KiB
connect.facebook.net/en_US/fbevents.js96.5 KiB33.5 KiB
www.si.edu/core/assets/vendor/jquery/jquery.min.js?v=3.7.141.7 KiB31.9 KiB
www.si.edu/core/assets/vendor/jquery/jquery.min.js?v=3.7.141.7 KiB30.2 KiB
www.si.edu/core/assets/vendor/jquery/jquery.min.js?v=3.7.141.7 KiB27.7 KiB
static.fundraiseup.com/checkout-styles.fab72e48733dfd10.js22.3 KiB22.3 KiB
static.fundraiseup.com/checkout-styles.fab72e48733dfd10.js22.3 KiB22.3 KiB
cdn.fundraiseup.com/widget/AVCYLAJJ64.3 KiB22.0 KiB
ucm-us.verint-cdn.com/files/sites/smithsonian/live/sdk.js41.4 KiB21.4 KiB
cdn.fundraiseup.com/widget/AVCYLAJJ64.3 KiB21.1 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 Evaluation1.3 s
Other464 ms
Script Parsing & Compilation265 ms
Style & Layout203 ms
Rendering56 ms
Parse HTML & CSS38 ms
Garbage Collection32 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.

Why this matters

Performance issues directly impact user engagement and conversion rates.

Estimated savings: 0.0 ms 16.1 KiB
URLTransfer SizeEst Savings
/sites/default/files/css/css_5xhAlRvn6wV5JITQK6SeFSwZ-en7...23.5 KiB16.1 KiB

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
static.fundraiseup.com/checkout.9e2624d0be733d7f.js410.4 KiB
www.gstatic.com/recaptcha/releases/gTpTIWhbKpxADzTzkcabhXN4/recaptcha__en.js362.4 KiB
www.gstatic.com/recaptcha/releases/gTpTIWhbKpxADzTzkcabhXN4/recaptcha__en.js361.9 KiB
www.googletagmanager.com/gtm.js?id=GTM-TT2JWKJ171.3 KiB
www.googletagmanager.com/gtag/js?id=G-ENWSWPLJYD&cx=c&gtm=4e64h1146.7 KiB
www.googletagmanager.com/gtag/js?id=AW-971586094&cx=c&gtm=4e64h1144.7 KiB
www.googletagmanager.com/gtag/js?id=AW-16464893431&cx=c&gtm=4e64h1143.7 KiB
static.fundraiseup.com/elements-langs-vendors.86315bee0669542d.js139.6 KiB
/sites/default/files/styles/hero_default/public/page_bann...115.2 KiB
static.fundraiseup.com/checkout-sentry-vendor.dda4c7629502a974.js111.8 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
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.

●Max Potential First Input Delay 80 ms
●Layout shift culprits
●Optimize DOM size
●LCP breakdown
●Modern HTTP
●Optimize viewport for mobile
●Minify CSS
●User Timing marks and measures 5 user timings
●JavaScript execution time 1.2 s
●Avoid long main-thread tasks 7 long tasks found
●Avoid non-composited animations 35 animated elements found
●Page didn't prevent back/forward cache restoration
●Network Requests
●Network Round Trip Times 110 ms
●Server Backend Latencies 90 ms
●Tasks
●Diagnostics
●Metrics
●Screenshot Thumbnails
●Final Screenshot
●Script Treemap Data
●Resources Summary
●Initial server response time was short Root document took 40 ms
●Avoid large layout shifts 2 layout shifts found
○INP breakdown
100

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.

○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-*]` attributes match their roles
●`[aria-hidden="true"]` is not present on the document `<body>`
●`[role]`s have all required `[aria-*]` attributes
●Elements with an ARIA `[role]` that require children to contain a specific `[role]` have all required children.
●`[role]`s are contained by their required parent element
●`[role]` values are valid
●`[aria-*]` attributes have valid values
●`[aria-*]` attributes are valid and not misspelled
●Buttons have an accessible name
●Image elements have `[alt]` attributes
●`[user-scalable="no"]` is not used in the `<meta name="viewport">` element and the `[maximum-scale]` attribute is not less than 5.
●ARIA attributes are used as specified for the element's role
●`[aria-hidden="true"]` elements do not contain focusable descendents
●Elements use only permitted ARIA attributes
●Background and foreground colors have a sufficient contrast ratio
●Document has a `<title>` element
●`<frame>` or `<iframe>` elements have a title
●`<html>` element has a `[lang]` attribute
●`<html>` element has a valid value for its `[lang]` attribute
●Links are distinguishable without relying on color.
●Links have a discernible name
●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.
●Heading elements appear in a sequentially-descending order
●Document has a main landmark.
●Deprecated ARIA roles were not used
●ARIA IDs are unique
●Uses ARIA roles only on compatible elements
●Elements with visible text labels have matching accessible names.
○`[accesskey]` values are unique
○`button`, `link`, and `menuitem` elements have accessible names
○Elements with `role="dialog"` or `role="alertdialog"` have accessible names.
○ARIA input fields 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 toggle fields have accessible names
○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
○No form fields have multiple labels
○`<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
○Form elements have associated labels
○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.
○`[lang]` attributes have a valid value
○`<video>` elements contain a `<track>` element with `[kind="captions"]`
○Tables have different content in the summary attribute and `<caption>`.
○All heading elements contain content.
○Image elements do not have `[alt]` attributes that are redundant text.
○Identical links have the same purpose.
○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.
73

Best Practices

General

Deprecated APIs will eventually be removed from the browser. Learn more about deprecated APIs.

Why this matters

Performance issues directly impact user engagement and conversion rates.

Deprecation / WarningSource
SharedStorage
www.si.edu/cdn-cgi/challenge-platform/scripts/jsd/main.js
StorageType.persistent is deprecated. Please use standardized navigator.storage instead.
www.si.edu/cdn-cgi/challenge-platform/scripts/jsd/main.js
Fledge
www.si.edu/cdn-cgi/challenge-platform/scripts/jsd/main.js
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

Why this matters

Performance issues directly impact user engagement and conversion rates.

SourceDescription
www.si.edu/
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.

Why this matters

Performance issues directly impact user engagement and conversion rates.

Issue type
Content security policy
●Uses HTTPS
●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
●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
●Page has valid source maps
○Redirects HTTP traffic to HTTPS
○Mitigate clickjacking with XFO or CSP
100

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.

○Structured data is valid
●Page isn’t blocked from indexing
●Document has a `<title>` element
●Document has a meta description
●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`

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