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Performance

· 14 checks — Lighthouse + waterfall + sustainability rolled into one auditable list.
SCORE
93
GRADE
A
FIX
0
REVIEW
4
PASS
8
INFO
2

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.
100
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.
100
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.

288 ms

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

456 ms

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

18 ms

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

0.005

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

288 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.

624 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
8 PASS 4 REVIEW
B
Image Optimization
4 images, 0 KB saveable
REVIEW
4 images, 0 KB saveable
Warning::
https://redux.js.org/img/redux.svg is missing width/height — may cause layout shift
Set explicit width and height to prevent CLS.
Warning::
https://redux.js.org/img/course-callout-mid.svg is missing width/height — may cause layout shift
Set explicit width and height to prevent CLS.
Warning::
https://www.netlify.com/img/global/badges/netlify-... is missing width/height — may cause layout shift
Set explicit width and height to prevent CLS.
4 images 3 KB
0 oversized -0 KB
2 legacy format
3 missing dimensions CLS risk

Set explicit width and height to prevent CLS.

Why this matters

Image without explicit width/height — browser can't reserve space; CLS jumps when image loads.

Source: web.dev / Core Web Vitals

Set explicit width and height to prevent CLS.

Why this matters

Image without explicit width/height — browser can't reserve space; CLS jumps when image loads.

Source: web.dev / Core Web Vitals

Set explicit width and height to prevent CLS.

Why this matters

Image without explicit width/height — browser can't reserve space; CLS jumps when image loads.

Source: web.dev / Core Web Vitals

B
JS Bundles
30 scripts, 50 KB unused
REVIEW
30 scripts, 50 KB unused
Warning::
https://redux.js.org/assets/js/main.869dfa69.js: 50 KB unused (36%)
Consider code splitting or tree shaking to reduce unused code.
Info::
Total unused JavaScript: 50 KB
50 KB unused JavaScript

Downloaded but never executed on this page.

ScriptSizeUnusedMinifiedParty
https://redux.js.org/assets/js/main.869dfa69.js140 KB50 KB (36%)✓1st
https://redux.js.org/assets/js/6cf0a46d.f6d2a068.js2 KB—✓1st
https://redux.js.org/assets/js/2756.2a40f883.js5 KB—✓1st
https://redux.js.org/assets/js/c4f5d8e4.7180e135.js4 KB—✓1st
https://redux.js.org/assets/js/a7456010.7e3226f2.js0 KB—✓1st
https://redux.js.org/assets/js/c4f5d8e4.7180e135.js0 KB—✓1st
https://redux.js.org/assets/js/a7456010.7e3226f2.js0 KB—✓1st
https://redux.js.org/assets/js/5e95c892.7824562f.js0 KB—✓1st
https://redux.js.org/assets/js/aba21aa0.0aa4e8d5.js0 KB—✓1st
https://redux.js.org/assets/js/a7bd4aaa.42c83445.js1 KB—✓1st

Consider code splitting or tree shaking to reduce unused code.

Why this matters

This bundle has high unused code — code-split or tree-shake to ship only what executes.

Source: web.dev / Lighthouse coverage

C
Green Hosting
Action
Whether the site is served from green-energy infrastructure
REVIEW

Green Hosting

No green hosting detected

B
HTTP Caching
public,max-age=0,must-revalidate
REVIEW
public,max-age=0,must-revalidate
Info::
Cache-Control header is set
Got: public,max-age=0,must-revalidate
Info::
ETag present — enables conditional (304) responses
Cache-Control

public,max-age=0,must-revalidate

DirectiveValueMeaning
public—Any cache may store this response
max-age0Cache for 0 seconds
must-revalidate—Must recheck with server after expiry
A+
Page Weight Budget
359 KB transferred, 42 requests
PASS
359 KB transferred, 42 requests
Info::
Page weighs 841 KB (359 KB transferred)
Info::
42 HTTP requests
Info::
Estimated 0.07 g CO2 per page load
359 KB / 2.4 MB budget
359 KB transferred
42 requests
0.07 g CO2 per page load
JavaScript 197.5 KiB 55%
Other 71.0 KiB 20%
Other 66.3 KiB 18%
CSS 14.9 KiB 4%
HTML 6.0 KiB 2%
Images 3.4 KiB 1%
Other 0 B 0%
0 2.4 MB 4.9 MB
Under budget
A+
Third-Party Impact
1% third-party, 0 ms blocking
PASS
1% third-party, 0 ms blocking
Info::
Third-party code accounts for 1% of page weight (2.1 KiB of 359.1 KiB)
Info::
Third-party blocking time is low (0 ms)
99%
First-party Third-party
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+
JS Execution Cost
299ms total JS execution
PASS
299ms total JS execution
Info::
https://redux.js.org/assets/js/main.869dfa69.js: 210ms CPU time
Info::
Unattributable: 89ms CPU time
Info::
Third-party scripts: 89ms (30% of total)

Main Thread Breakdown

Script Evaluation 64% Other 18% Style & Layout 7% Script Parsing & Compilation 6%
ScriptTotalScriptingParse/CompileParty
https://redux.js.org/assets/js/main.869dfa69.js210ms187ms16ms1st
Unattributable89ms26ms0ms3rd
A+
Font Loading
No web fonts (system fonts)
PASS
No web fonts (system fonts)
Info::
No web fonts loaded — system fonts are fastest
No web fonts loaded — system fonts are optimal.
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
Network Waterfall
42 requests over 0ms
INFO

Performance analysis not available for this result.

Third-Party Script Cost
Per-script blocking time, transfer cost, and cache headers
INFO
30% of JavaScript execution is third-party
First-party Third-party 89ms · 0KB · $1/mo
Unattributable
Other
Optional
Execution 89ms
Transfer 0 KB
Monthly Cost $1/mo

How third-party costs are calculated

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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