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https://lib.ru

Performance

· 14 checks — Lighthouse + waterfall + sustainability rolled into one auditable list.
SCORE
100
GRADE
A+
FIX
1
REVIEW
1
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.
50
Accessibility Measures how accessible the page is for users with disabilities. Checks color contrast, ARIA labels, and semantic HTML.
69
Best Practices Checks for modern web development best practices including HTTPS, no console errors, and secure JavaScript.
83
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.

257 ms

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

257 ms

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

0 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.

315 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.

257 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 1 REVIEW 1 FIX
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.
Info::
Last-Modified header present

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
9 KB transferred, 6 requests
PASS
9 KB transferred, 6 requests
Info::
Page weighs 22 KB (9 KB transferred)
Info::
6 HTTP requests
Info::
Estimated 0.00 g CO2 per page load
9 KB / 2.4 MB budget
9 KB transferred
6 requests
0.00 g CO2 per page load
HTML 8.1 KiB 90%
Other 559 B 6%
Images 391 B 4%
0 2.4 MB 4.9 MB
Under budget
A+
Third-Party Impact
4% third-party, 0 ms blocking
PASS
4% third-party, 0 ms blocking
Info::
Third-party code accounts for 4% of page weight (391 B of 9.1 KiB)
Info::
Third-party blocking time is low (0 ms)
96%
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+
Image Optimization
4 images, 0 KB saveable
PASS
4 images, 0 KB saveable
Info::
All images are well-optimized
4 images 0 KB
0 oversized -0 KB
1 legacy format
0 missing dimensions CLS risk
A+
JS Execution Cost
62ms total JS execution
PASS
62ms total JS execution
Info::
https://lib.ru/: 62ms CPU time

Main Thread Breakdown

Style & Layout 50% Other 30% Rendering 13% Script Evaluation 4%
ScriptTotalScriptingParse/CompileParty
https://lib.ru/62ms1ms0ms1st
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
No JavaScript
PASS
No JavaScript
Info::
No JavaScript bundles
No JavaScript files loaded.
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
6 resources · 9 KB · 0 KB savings available
PASS
6 resources · 9 KB · 0 KB savings available
Info::
Within 1MB page-weight target
Got: 9 KB
Info::
4 third-party resources (4% of weight)
6 resources · 9.1 KiB · 4 third-party Within 1MB page-weight target
Document 90% · 8.1 KiB
Image 10% · 950 B
Network Waterfall
6 requests over 588ms
INFO
0 ms 200 ms 400 ms 600 ms FCP 257 ms LCP 257 mshttps://lib.ru// https://lib.ru/ — 200 — 8.1 KiB — 243 ms — http/1.1https://top.list.ru/counter?id=105282;t=99top.list.ru/counter?id=105282;t=99 https://top.list.ru/counter?id=105282;t=99 — -1 — 0 B — 153 ms — https://top100-images.rambler.ru/top100/b0.giftop100-images.rambler.ru/top100/b0.... https://top100-images.rambler.ru/top100/b0.gif — -1 — 0 B — 267 ms — https://counter.rambler.ru/top100.cnt?59291counter.rambler.ru/top100.cnt?59291 https://counter.rambler.ru/top100.cnt?59291 — 200 — 391 B — 212 ms — h2https://u083.69.spylog.com/cnt?p=0u083.69.spylog.com/cnt?p=0 https://u083.69.spylog.com/cnt?p=0 — -1 — 0 B — 55 ms — https://lib.ru/favicon.ico/favicon.ico https://lib.ru/favicon.ico — 200 — 559 B — 66 ms — http/1.1
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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