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Performance

· 14 checks — Lighthouse + waterfall + sustainability rolled into one auditable list.
SCORE
69
GRADE
D
FIX
2
REVIEW
0
PASS
11
INFO
1

Performance-focused optimization plan with CWV assessment, top offenders, and time estimates

Mobile Desktop
100
Performance Overall performance score (0–100) based on Core Web Vitals and other metrics. 90+ is good.
90
Accessibility Measures how accessible the page is for users with disabilities. Checks color contrast, ARIA labels, and semantic HTML.
96
Best Practices Checks for modern web development best practices including HTTPS, no console errors, and secure JavaScript.
80
SEO Measures basic SEO optimizations: meta tags, crawlability, link text, and mobile friendliness.

First Contentful Paint First Contentful Paint — how long until the browser renders the first piece of content. Under 1.8s is good.

422 ms

Largest Contentful Paint Largest Contentful Paint — how long until the largest visible element loads. Under 2.5s is good.

422 ms

Total Blocking Time Total Blocking Time — total time the main thread was blocked, preventing user input. Under 200ms is good.

3 ms

Cumulative Layout Shift Cumulative Layout Shift — measures visual stability. How much the page layout shifts during loading. Under 0.1 is good.

0.001

Speed Index Speed Index — how quickly content is visually displayed during load. Under 3.4s is good.

465 ms

Time to Interactive Time to Interactive — how long until the page is fully interactive and responds to user input. Under 3.8s is good.

604 ms

Page Load Progression

375 ms
750 ms
1.1 s
1.5 s
1.9 s
2.2 s
2.6 s
3.0 s
Checks
14
11 PASS 2 FIX
D
Third-Party Impact
Action
68% third-party, 0 ms blocking
FIX
68% third-party, 0 ms blocking
Warning::
Third-party code accounts for 68% of page weight (429.0 KiB of 631.5 KiB)
Info::
Third-party blocking time is low (0 ms)
32%
68%
First-party Third-party
D
HTTP Caching
Action
no-store (uncacheable)
FIX
no-store (uncacheable)
Info::
Cache-Control: no-store prevents all caching
Intentional for dynamic content, but increases server load for every page view.
Got: private, max-age=0, no-store, no-cache, must-revalidate, post-check=0, pre-check=0
Info::
No ETag or Last-Modified header
Conditional requests (304 Not Modified) are not possible without validators.
Cache-Control

private, max-age=0, no-store, no-cache, must-revalidate, post-check=0, pre-check=0

DirectiveValueMeaning
private—Only browser cache, not CDN/proxy
max-age0Cache for 0 seconds
no-store—Never cache this response
no-cache—Cache but always revalidate first
must-revalidate—Must recheck with server after expiry
post-check0
pre-check0
A+
Page Weight Budget
632 KB transferred, 18 requests
PASS
632 KB transferred, 18 requests
Info::
Page weighs 1.1 MB (632 KB transferred)
Info::
18 HTTP requests
Info::
Estimated 0.13 g CO2 per page load
632 KB / 2.4 MB budget
632 KB transferred
18 requests
0.13 g CO2 per page load
Other 311.4 KiB 49%
HTML 211.9 KiB 34%
JavaScript 90.5 KiB 14%
Fonts 14.9 KiB 2%
Other 1.7 KiB 0%
Images 1.2 KiB 0%
Other 61 B 0%
0 2.4 MB 4.9 MB
Under budget
A+
Text Compression
All text resources are compressed
PASS
All text resources are compressed
Info::
All text resources are compressed
All text resources are properly compressed.
A
Image Optimization
2 images, 0 KB saveable
PASS
2 images, 0 KB saveable
Info::
All images are well-optimized
2 images 1 KB
0 oversized -0 KB
2 legacy format
0 missing dimensions CLS risk
A+
JS Execution Cost
248ms total JS execution
PASS
248ms total JS execution
Info::
https://quizlet.com/cdn-cgi/challenge-platform/h/b...: 248ms CPU time

Main Thread Breakdown

Script Evaluation 78% Other 14%
ScriptTotalScriptingParse/CompileParty
https://quizlet.com/cdn-cgi/challenge-platform/h/b/orchestrate/chl_page/v1?ray=9efff7778fb94aff248ms236ms4ms1st
A+
Font Loading
1 fonts (15 KB)
PASS
1 fonts (15 KB)
Info::
1 font(s) use font-display: swap (FOUT risk but functional)

Web fonts

1

15 KB total

Render-blocking

0

of 1

Dominant font-display

swap

Most common across fonts

Font loading timeline
Transfer FOIT (block) FOUT (swap)
0 ms 500 ms 1.0 s FCP 422 ms LCP 422 msdata:application/font-woff2;charset=utf-8;base64,d09GMgABAAAAADt8ABMAAAAAp7gAADsMAAIAQgAAAAAAAAAAAA…font-woff2;charset=utf-... data:application/font-woff2;charset=utf-8;base64,d09GMgABAAAAADt8ABMAAAAAp7gAADsMAAIAQgAAAAAAAAAAAA… — 14.9 KiB — 1 ms — font-display: swap
font-woff2;charset=utf-... woff2 swap
Size 15 KB
Load time 1 ms
Start 159 ms
Risk FOUT — text flashes from fallback to web font
Optimization checklist
  • Preload critical fonts (priority=high)
  • Use woff2 format for all fonts
  • Set font-display to swap, optional, or fallback
  • Subset large fonts (≤100 KB each)
A+
JS Bundles
8 scripts, 0 KB unused
PASS
8 scripts, 0 KB unused
0 KB unused JavaScript

Downloaded but never executed on this page.

ScriptSizeUnusedMinifiedParty
https://quizlet.com/cdn-cgi/challenge-platform/h/b/orchestrate/chl_page/v1?ray=9efff7778fb94aff73 KB—✓1st
blob:https://quizlet.com/d28fa12d-1cbf-47f9-ad6c-453ac5b256ab0 KB—✓3rd
https://challenges.cloudflare.com/turnstile/v0/b/0b8fb825cb67/api.js?onload=cFRiY3&render=explicit17 KB—✓3rd
blob:https://quizlet.com/b5167c96-0157-4db8-a78c-0fdc7a613dc0-0 KB—✓3rd
blob:https://challenges.cloudflare.com/c6ce80ab-27d5-4098-bce4-13e58e4c07cd0 KB—✓3rd
blob:https://challenges.cloudflare.com/4273691b-0e79-4ee3-be21-ed508207ada5-0 KB—✓3rd
blob:https://challenges.cloudflare.com/4273691b-0e79-4ee3-be21-ed508207ada5-0 KB—✓3rd
blob:https://challenges.cloudflare.com/0608b586-7095-4b0c-a768-342090a9811f-0 KB—✓3rd
A+
Resource Caching
All resources properly cached
PASS
All resources properly cached
Info::
No caching issues found
All static resources have appropriate caching headers.
A+
Critical Rendering Path
No render-blocking resources
PASS
No render-blocking resources
Info::
No render-blocking resources detected
A+
Resource Hints
No optimization needed
PASS
No optimization needed
Info::
No resource hint issues
A
Page Weight Inventory
18 resources · 632 KB · 0 KB savings available
PASS
18 resources · 632 KB · 0 KB savings available
Info::
Within 1MB page-weight target
Got: 632 KB
Warning::
14 third-party resources (68% of weight)
Info::
1 resources over 200KB
18 resources · 631.5 KiB · 14 third-party Within 1MB page-weight target
Other 50% · 313.1 KiB
Document 34% · 211.9 KiB
JavaScript 14% · 90.5 KiB
Font 2% · 14.9 KiB
Image 0% · 1.2 KiB
A+
Green Hosting
Whether the site is served from green-energy infrastructure
PASS

Green Hosting

This site is hosted on green energy infrastructure

Provider: Cloudflare

Network Waterfall
18 requests over 2742ms
INFO
0 ms 500 ms 1.0 s 1.5 s 2.0 s 2.5 s FCP 422 ms LCP 422 mshttps://quizlet.com// https://quizlet.com/ — 307 — 61 B — 86 ms — http/1.1https://quizlet.com// https://quizlet.com/ — 403 — 115.9 KiB — 42 ms — h2https://quizlet.com/cdn-cgi/challenge-platform/h/b/orchestrate/chl_page/v1?ray=9efff7778fb94aff/cdn-cgi/challenge-platform/h/b/orc... https://quizlet.com/cdn-cgi/challenge-platform/h/b/orchestrate/chl_page/v1?ray=9efff7778fb94aff — 200 — 73.0 KiB — 35 ms — h2data:application/font-woff2;charset=utf-8;base64,d09GMgABAAAAADt8ABMAAAAAp7gAADsMAAIAQgAAAAAAAAAAAA…data:application/font-woff2;charset... data:application/font-woff2;charset=utf-8;base64,d09GMgABAAAAADt8ABMAAAAAp7gAADsMAAIAQgAAAAAAAAAAAA… — 200 — 14.9 KiB — 1 ms — datablob:https://quizlet.com/d28fa12d-1cbf-47f9-ad6c-453ac5b256abquizlet.com/d28fa12d-1cbf-47f9-ad6c... blob:https://quizlet.com/d28fa12d-1cbf-47f9-ad6c-453ac5b256ab — -1 — 0 B — 0 ms — https://challenges.cloudflare.com/turnstile/v0/b/0b8fb825cb67/api.js?onload=cFRiY3&render=explicitchallenges.cloudflare.com/turnstile... https://challenges.cloudflare.com/turnstile/v0/b/0b8fb825cb67/api.js?onload=cFRiY3&render=explicit — 200 — 17.4 KiB — 83 ms — h3https://quizlet.com/cdn-cgi/challenge-platform/h/b/flow/ov1/3594160270:1776809553:LF-d7ov4rwlPFiaU1cNWhn-u54a_SCI9x1hbvxf-iHs/9efff7778fb94aff/BGFmhmdH4qRdIZFHCBS2LvjLHvOCZnUm5Xx1NccH2h8-1776812025-1.2.1.1-m2d1pRt.rcpxGzS5e4JT73sPzaC_Ie_dsVnrk4YnKxbgz4uzW3bcON1PGShfUXyM/cdn-cgi/challenge-platform/h/b/flo... https://quizlet.com/cdn-cgi/challenge-platform/h/b/flow/ov1/3594160270:1776809553:LF-d7ov4rwlPFiaU1cNWhn-u54a_SCI9x1hbvxf-iHs/9efff7778fb94aff/BGFmhmdH4qRdIZFHCBS2LvjLHvOCZnUm5Xx1NccH2h8-1776812025-1.2.1.1-m2d1pRt.rcpxGzS5e4JT73sPzaC_Ie_dsVnrk4YnKxbgz4uzW3bcON1PGShfUXyM — 200 — 13.4 KiB — 36 ms — h2blob:https://quizlet.com/b5167c96-0157-4db8-a78c-0fdc7a613dc0quizlet.com/b5167c96-0157-4db8-a78c... blob:https://quizlet.com/b5167c96-0157-4db8-a78c-0fdc7a613dc0 — 200 — -1 B — 23 ms — blobhttps://challenges.cloudflare.com/cdn-cgi/challenge-platform/h/b/turnstile/f/ov2/av0/rch/pihmb/0x4AAAAAAADnPIDROrmt1Wwj/light/fbE/new/normal?lang=autochallenges.cloudflare.com/cdn-cgi/c... https://challenges.cloudflare.com/cdn-cgi/challenge-platform/h/b/turnstile/f/ov2/av0/rch/pihmb/0x4AAAAAAADnPIDROrmt1Wwj/light/fbE/new/normal?lang=auto — 200 — 95.9 KiB — 97 ms — h3https://challenges.cloudflare.com/cdn-cgi/challenge-platform/h/b/cmg/1challenges.cloudflare.com/cdn-cgi/c... https://challenges.cloudflare.com/cdn-cgi/challenge-platform/h/b/cmg/1 — 200 — 208 B — 21 ms — h3blob:https://challenges.cloudflare.com/c6ce80ab-27d5-4098-bce4-13e58e4c07cdchallenges.cloudflare.com/c6ce80ab-... blob:https://challenges.cloudflare.com/c6ce80ab-27d5-4098-bce4-13e58e4c07cd — -1 — 0 B — 0 ms — https://challenges.cloudflare.com/cdn-cgi/challenge-platform/h/b/flow/ov1/1072627103:1776809555:BmIdi2STVtUVd1U8czSCHAzL_O0c577w2Xdp6OQL8uQ/9efff779efd18825/fVzGfQHfBw6zr750E.RVAxLOENYRa.lvb98pKY3Gj9k-1776812025-1.2.1.1-bcpNZ6aY8XMTMIwZ7u62973s03rIbAYlmzIxfzIo4EBrZJfjm96ClQCvVTHi7kAnchallenges.cloudflare.com/cdn-cgi/c... https://challenges.cloudflare.com/cdn-cgi/challenge-platform/h/b/flow/ov1/1072627103:1776809555:BmIdi2STVtUVd1U8czSCHAzL_O0c577w2Xdp6OQL8uQ/9efff779efd18825/fVzGfQHfBw6zr750E.RVAxLOENYRa.lvb98pKY3Gj9k-1776812025-1.2.1.1-bcpNZ6aY8XMTMIwZ7u62973s03rIbAYlmzIxfzIo4EBrZJfjm96ClQCvVTHi7kAn — 200 — 275.2 KiB — 140 ms — h3blob:https://challenges.cloudflare.com/4273691b-0e79-4ee3-be21-ed508207ada5challenges.cloudflare.com/4273691b-... blob:https://challenges.cloudflare.com/4273691b-0e79-4ee3-be21-ed508207ada5 — 200 — -1 B — 85 ms — blobblob:https://challenges.cloudflare.com/4273691b-0e79-4ee3-be21-ed508207ada5challenges.cloudflare.com/4273691b-... blob:https://challenges.cloudflare.com/4273691b-0e79-4ee3-be21-ed508207ada5 — 200 — -1 B — 12 ms — blobhttps://challenges.cloudflare.com/cdn-cgi/challenge-platform/h/b/d/9efff779efd18825/1776812026205/HkfUC7mHjyhlzwkchallenges.cloudflare.com/cdn-cgi/c... https://challenges.cloudflare.com/cdn-cgi/challenge-platform/h/b/d/9efff779efd18825/1776812026205/HkfUC7mHjyhlzwk — 200 — 995 B — 21 ms — h3https://challenges.cloudflare.com/cdn-cgi/challenge-platform/h/b/pat/9efff779efd18825/1776812026205/e0119b16c0871ef1c1bc1519f0427453a94ab38c368ef5f1cb756070c8fe3d96/78iscFpGlChE5Ndchallenges.cloudflare.com/cdn-cgi/c... https://challenges.cloudflare.com/cdn-cgi/challenge-platform/h/b/pat/9efff779efd18825/1776812026205/e0119b16c0871ef1c1bc1519f0427453a94ab38c368ef5f1cb756070c8fe3d96/78iscFpGlChE5Nd — 401 — 1.7 KiB — 21 ms — h3https://challenges.cloudflare.com/cdn-cgi/challenge-platform/h/b/flow/ov1/1072627103:1776809555:BmIdi2STVtUVd1U8czSCHAzL_O0c577w2Xdp6OQL8uQ/9efff779efd18825/fVzGfQHfBw6zr750E.RVAxLOENYRa.lvb98pKY3Gj9k-1776812025-1.2.1.1-bcpNZ6aY8XMTMIwZ7u62973s03rIbAYlmzIxfzIo4EBrZJfjm96ClQCvVTHi7kAnchallenges.cloudflare.com/cdn-cgi/c... https://challenges.cloudflare.com/cdn-cgi/challenge-platform/h/b/flow/ov1/1072627103:1776809555:BmIdi2STVtUVd1U8czSCHAzL_O0c577w2Xdp6OQL8uQ/9efff779efd18825/fVzGfQHfBw6zr750E.RVAxLOENYRa.lvb98pKY3Gj9k-1776812025-1.2.1.1-bcpNZ6aY8XMTMIwZ7u62973s03rIbAYlmzIxfzIo4EBrZJfjm96ClQCvVTHi7kAn — 200 — 22.8 KiB — 42 ms — h3blob:https://challenges.cloudflare.com/0608b586-7095-4b0c-a768-342090a9811fchallenges.cloudflare.com/0608b586-... blob:https://challenges.cloudflare.com/0608b586-7095-4b0c-a768-342090a9811f — 200 — -1 B — 15 ms — blob
HTML JavaScript CSS Images Fonts XHR/Fetch Other
All checks on this page are automated. Results are estimates - run targeted manual reviews when the score affects a release decision.

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