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Performance

· 16 checks — Lighthouse + waterfall + sustainability rolled into one auditable list.
SCORE
94
GRADE
A
FIX
2
REVIEW
1
PASS
12
INFO
1

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

Mobile Desktop
72
Performance Overall performance score (0–100) based on Core Web Vitals and other metrics. 90+ is good.
39
Accessibility Measures how accessible the page is for users with disabilities. Checks color contrast, ARIA labels, and semantic HTML.
100
Best Practices Checks for modern web development best practices including HTTPS, no console errors, and secure JavaScript.
82
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.

4.15 s

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

4.86 s

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

19 ms

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.

4.15 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.

4.86 s

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
16
12 PASS 1 REVIEW 2 FIX
D
Third-Party Impact
Action
99% third-party, 0 ms blocking
FIX
99% third-party, 0 ms blocking
Warning::
Third-party code accounts for 99% of page weight (104.6 KiB of 105.5 KiB)
Info::
Third-party blocking time is low (0 ms)
99%
First-party Third-party
F
HTTP Caching
Action
No cache headers
FIX
No cache headers
Warning::
No Cache-Control header found
Browsers will use heuristic caching, which can be unpredictable. Set explicit cache headers.

No Cache-Control header

Adding a Cache-Control header can significantly improve repeat-visit performance.

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

Green Hosting

No green hosting detected

A+
Page Weight Budget
105 KB transferred, 11 requests
PASS
105 KB transferred, 11 requests
Info::
Page weighs 300 KB (105 KB transferred)
Info::
11 HTTP requests
Info::
Estimated 0.02 g CO2 per page load
105 KB / 2.4 MB budget
105 KB transferred
11 requests
0.02 g CO2 per page load
JavaScript 68.1 KiB 65%
Images 27.5 KiB 26%
CSS 5.0 KiB 5%
HTML 3.1 KiB 3%
Other 1.5 KiB 1%
Other 302 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
Warning::
https://gw.alicdn.com/tfs/TB13sdSRHr1gK0jSZFDXXb9y... is missing width/height — may cause layout shift
Set explicit width and height to prevent CLS.
2 images 27 KB
0 oversized -0 KB
0 legacy format
1 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

A+
JS Execution Cost
No JS execution data
PASS
No JS execution data
Info::
No significant JS execution detected
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+
JS Bundles
4 scripts, 0 KB unused
PASS
4 scripts, 0 KB unused
0 KB unused JavaScript

Downloaded but never executed on this page.

ScriptSizeUnusedMinifiedParty
https://g.alicdn.com/mtb/lib-flexible/0.3.2/flexible.js1 KB—✓3rd
https://g.alicdn.com/sd/punish/0.0.1/qrcode.min.js7 KB—✓3rd
https://g.alicdn.com/bsop-static/sufei-punish/0.1.106/build/punishpage.min.js35 KB—✓3rd
https://g.alicdn.com/trace/trace/1.3.22/??sdk.js,resourceError-plugin.js,perf-plugin.js24 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
11 resources · 105 KB · 0 KB savings available
PASS
11 resources · 105 KB · 0 KB savings available
Info::
Within 1MB page-weight target
Got: 105 KB
Warning::
10 third-party resources (99% of weight)
11 resources · 105.5 KiB · 10 third-party Within 1MB page-weight target
JavaScript 65% · 68.1 KiB
Image 28% · 29.3 KiB
CSS 5% · 5.0 KiB
Document 3% · 3.1 KiB
A+
Render-Blocking Resources
No render-blocking resources detected
PASS
No render-blocking resources detected
Info::
No render-blocking resources detected in <head>
A+
Third-Party Resources
No third-party resources detected
PASS
No third-party resources detected
Network Waterfall
11 requests over 3470ms
INFO
0 ms 1.0 s 2.0 s 3.0 s 4.0 s 5.0 s FCP 4.2 s LCP 4.9 shttps://youku.com// https://youku.com/ — 200 — 942 B — 705 ms — h2https://bixi.alicdn.com/punish/punish:resource:template:heyiSpace:default_37129713.html?qrcode=2scJrYBepuqXv-ML0aohzQ|aefEsw|TDry5Q_0|cloud_ip_bl|0&uuid=dac709ad805ea6ea97bfe30bd1aa21cd&action=deny&origin=https%3A%2F%2Fyouku.com%3A443bixi.alicdn.com/punish/punish:resou... https://bixi.alicdn.com/punish/punish:resource:template:heyiSpace:default_37129713.html?qrcode=2scJrYBepuqXv-ML0aohzQ|aefEsw|TDry5Q_0|cloud_ip_bl|0&uuid=dac709ad805ea6ea97bfe30bd1aa21cd&action=deny&origin=https%3A%2F%2Fyouku.com%3A443 — 200 — 2.2 KiB — 1.4 s — h2https://g.alicdn.com/mtb/lib-flexible/0.3.2/flexible.jsg.alicdn.com/mtb/lib-flexible/0.3.2... https://g.alicdn.com/mtb/lib-flexible/0.3.2/flexible.js — 200 — 1.5 KiB — 20 ms — h2https://g.alicdn.com/sd/punish/0.0.1/qrcode.min.jsg.alicdn.com/sd/punish/0.0.1/qrcode... https://g.alicdn.com/sd/punish/0.0.1/qrcode.min.js — 200 — 7.1 KiB — 25 ms — h2https://g.alicdn.com/bsop-static/sufei-punish/0.1.106/build/main.cssg.alicdn.com/bsop-static/sufei-puni... https://g.alicdn.com/bsop-static/sufei-punish/0.1.106/build/main.css — 200 — 5.0 KiB — 8 ms — h2https://g.alicdn.com/bsop-static/sufei-punish/0.1.106/build/punishpage.min.jsg.alicdn.com/bsop-static/sufei-puni... https://g.alicdn.com/bsop-static/sufei-punish/0.1.106/build/punishpage.min.js — 200 — 35.4 KiB — 25 ms — h2https://g.alicdn.com/trace/trace/1.3.22/??sdk.js,resourceError-plugin.js,perf-plugin.jsg.alicdn.com/trace/trace/1.3.22/??s... https://g.alicdn.com/trace/trace/1.3.22/??sdk.js,resourceError-plugin.js,perf-plugin.js — 200 — 24.1 KiB — 23 ms — h2https://gw.alicdn.com/tfs/TB1ugm9f5cKOu4jSZKbXXc19XXa-356-76.pnggw.alicdn.com/tfs/TB1ugm9f5cKOu4jSZ... https://gw.alicdn.com/tfs/TB1ugm9f5cKOu4jSZKbXXc19XXa-356-76.png — 200 — 5.8 KiB — 17 ms — h2https://gw.alicdn.com/tfs/TB13sdSRHr1gK0jSZFDXXb9yVXa-400-400.pnggw.alicdn.com/tfs/TB13sdSRHr1gK0jSZ... https://gw.alicdn.com/tfs/TB13sdSRHr1gK0jSZFDXXb9yVXa-400-400.png — 200 — 21.6 KiB — 15 ms — h2https://bixi.alicdn.com/favicon.icobixi.alicdn.com/favicon.ico https://bixi.alicdn.com/favicon.ico — 200 — 1.5 KiB — 7 ms — h2https://s-gm.mmstat.com/arms.1.2s-gm.mmstat.com/arms.1.2 https://s-gm.mmstat.com/arms.1.2 — 200 — 302 B — 1.2 s — h2
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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