https://serebrokubachi.ru
Performance
· 24 checks — Lighthouse + waterfall + sustainability rolled into one auditable list.SCORE
87
GRADE
B
FIX
1
REVIEW
8
PASS
10
INFO
5
Performance-focused optimization plan with CWV assessment, top offenders, and time estimates
98
93
96
100
First Contentful Paint First Contentful Paint — how long until the browser renders the first piece of content. Under 1.8s is good.
465 ms
Largest Contentful Paint Largest Contentful Paint — how long until the largest visible element loads. Under 2.5s is good.
566 ms
Total Blocking Time Total Blocking Time — total time the main thread was blocked, preventing user input. Under 200ms is good.
28 ms
Cumulative Layout Shift Cumulative Layout Shift — measures visual stability. How much the page layout shifts during loading. Under 0.1 is good.
0.007
Speed Index Speed Index — how quickly content is visually displayed during load. Under 3.4s is good.
1.52 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.
1.55 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 sChecks
2410 PASS 8 REVIEW 1 FIX
FHTTP CachingActionNo cache headersFIX
HTTP Caching
ActionNo cache headers
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.
BPage Weight Budget1.1 MB transferred, 86 requestsREVIEW
Page Weight Budget
1.1 MB transferred, 86 requests
1.1 MB transferred, 86 requests
Info::
Page weighs 2.3 MB (1.1 MB transferred)
Info::
86 HTTP requests
Info::
Estimated 0.23 g CO2 per page load
1.1 MB transferred
86 requests
0.23 g CO2 per page load
Images 463.0 KiB 41%
JavaScript 448.4 KiB 40%
Other 69.4 KiB 6%
Fonts 64.1 KiB 6%
HTML 43.8 KiB 4%
CSS 36.8 KiB 3%
Other 2.2 KiB 0%
Other 866 B 0%
0 2.4 MB 4.9 MB
Under budget
BImage Optimization50 images, 0 KB saveableREVIEW
Image Optimization
50 images, 0 KB saveable
50 images, 0 KB saveable
Info::
All images are well-optimized
50 images 463 KB
0 oversized -0 KB
24 legacy format
0 missing dimensions CLS risk
BJS Execution Cost705ms total JS executionREVIEW
JS Execution Cost
705ms total JS execution
705ms total JS execution
Warning::
https://serebrokubachi.ru/: 332ms CPU time
Info::
Unattributable: 147ms CPU time
Info::
https://www.googletagmanager.com/gtag/js?id=G-R35C...: 108ms CPU time
Info::
https://mc.yandex.com/metrika/tag.js: 65ms CPU time
Info::
https://www.googletagmanager.com/gtm.js?id=GTM-TVL...: 53ms CPU time
Info::
Third-party scripts: 226ms (32% of total)
Main Thread Breakdown
Script Evaluation 34% Other 30% Style & Layout 18% Rendering 8% Script Parsing & Compilation 5%
| Script | Total | Scripting | Parse/Compile | Party |
|---|---|---|---|---|
| https://serebrokubachi.ru/ | 332ms | 36ms | 6ms | 1st |
| Unattributable | 147ms | 6ms | 0ms | 1st |
| https://www.googletagmanager.com/gtag/js?id=G-R35CE3JWHQ&cx=c>m=4e6aj1h2 | 108ms | 90ms | 12ms | 3rd |
| https://mc.yandex.com/metrika/tag.js | 65ms | 57ms | 5ms | 3rd |
| https://www.googletagmanager.com/gtm.js?id=GTM-TVLPKZ9C | 53ms | 42ms | 11ms | 3rd |
CJS BundlesAction14 scripts, 173 KB unusedREVIEW
JS Bundles
Action14 scripts, 173 KB unused
14 scripts, 173 KB unused
Warning::
https://www.googletagmanager.com/gtag/js?id=G-R35C...: 72 KB unused (38%)
Consider code splitting or tree shaking to reduce unused code.
Warning::
https://www.googletagmanager.com/gtm.js?id=GTM-TVL...: 64 KB unused (48%)
Consider code splitting or tree shaking to reduce unused code.
Warning::
https://mc.yandex.com/metrika/tag.js: 36 KB unused (53%)
Consider code splitting or tree shaking to reduce unused code.
Info::
Total unused JavaScript: 173 KB
173 KB unused JavaScript
Downloaded but never executed on this page.
| Script | Size | Unused | Minified | Party |
|---|---|---|---|---|
| https://www.googletagmanager.com/gtag/js?id=G-R35CE3JWHQ&cx=c>m=4e6aj1h2 | 189 KB | 72 KB (38%) | ✓ | 3rd |
| https://www.googletagmanager.com/gtm.js?id=GTM-TVLPKZ9C | 136 KB | 64 KB (48%) | ✓ | 3rd |
| https://mc.yandex.com/metrika/tag.js | 69 KB | 36 KB (53%) | ✓ | 3rd |
| https://serebrokubachi.ru/wp-content/plugins/duracelltomi-google-tag-manager/build/gtm4wp-ecommerce-generic.js?ver=2.0.6 | 1 KB | — | ✓ | 1st |
| https://serebrokubachi.ru/wp-content/litespeed/js/4d5bf675c449f0a3a201a99ece1eb840.js?ver=f03cc | 19 KB | — | ✓ | 1st |
| https://serebrokubachi.ru/wp-content/litespeed/js/13ccc689bfa1e3b0e0896b979c3b1ec3.js?ver=a482a | 1 KB | — | ✓ | 1st |
| https://serebrokubachi.ru/wp-content/plugins/litespeed-cache/assets/js/css_async.min.js | 1 KB | — | ✓ | 1st |
| https://serebrokubachi.ru/wp-content/themes/flatsome/assets/js/flatsome.js?ver=c70e5a9a66ada87bcb37 | 18 KB | — | ✓ | 1st |
| https://serebrokubachi.ru/wp-content/themes/flatsome/assets/js/chunk.slider.js?ver=3.20.11 | 13 KB | — | ✓ | 1st |
| https://serebrokubachi.ru/wp-content/themes/flatsome/assets/js/chunk.popups.js?ver=3.20.11 | 7 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
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
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
BDocument CompressionDocument response uses gzip; brotli would be ~20% smallerREVIEW
Document Compression
Document response uses gzip; brotli would be ~20% smaller
Document response uses gzip; brotli would be ~20% smaller
Info::
Main HTML response uses gzip (brotli would be ~20% smaller)
All current browsers support brotli. Most CDNs (Cloudflare, Fastly, AWS CloudFront, Vercel, Netlify) can switch from gzip to brotli with a single config flag. Origin servers (nginx, Apache) need a brotli module compiled in -- nginx-brotli or Apache mod_brotli.
BMain HTML Cache-ControlNo Cache-Control header on main HTML responseREVIEW
Main HTML Cache-Control
No Cache-Control header on main HTML response
No Cache-Control header on main HTML response
Info::
Main HTML response has no Cache-Control header
Without an explicit Cache-Control, browsers fall back to heuristic caching (~10% of Last-Modified age). Set `Cache-Control: no-cache` or `max-age=300` for HTML to control freshness explicitly -- prevents stale auth state and SPA shell drift.
BServer-Timing ObservabilityNo Server-Timing header foundREVIEW
Server-Timing Observability
No Server-Timing header found
No Server-Timing header found
Info::
No Server-Timing header found
Server-Timing exposes backend timing breakdowns to browser DevTools (e.g., `db: 45ms; render: 120ms; cache: 2ms`). Useful for diagnosing slow pages without backend log access. Most modern frameworks (Next.js, Cloudflare Workers, Fastly) emit it automatically; absence on a managed platform usually means telemetry headers are stripped at the edge.
CGreen HostingActionWhether the site is served from green-energy infrastructureREVIEW
Green Hosting
ActionWhether the site is served from green-energy infrastructure
Green Hosting
No green hosting detected
AThird-Party Impact36% third-party, 0 ms blockingPASS
Third-Party Impact
36% third-party, 0 ms blocking
36% third-party, 0 ms blocking
Info::
Third-party code accounts for 36% of page weight (402.4 KiB of 1.1 MiB)
Info::
Third-party blocking time is low (0 ms)
64%
36%
First-party Third-party
A+Text CompressionAll text resources are compressedPASS
Text Compression
All text resources are compressed
All text resources are compressed
Info::
All text resources are compressed
All text resources are properly compressed.
A+Font Loading5 fonts (64 KB)PASS
Font Loading
5 fonts (64 KB)
5 fonts (64 KB)
Info::
5 font(s) use font-display: swap (FOUT risk but functional)
Web fonts
5
64 KB total
Render-blocking
0
of 5
Dominant font-display
swap
Most common across fonts
Font loading timeline
Transfer FOIT (block) FOUT (swap)
S6uyw4BMUTPHjx4wXg.woff2 woff2 swap
Size 23 KB
Load time 94 ms
Start 1.9 s
Risk FOUT — text flashes from fallback to web font
fl-icons.woff2 woff2 swap
Size 7 KB
Load time 99 ms
Start 1.9 s
Risk FOUT — text flashes from fallback to web font
S6u9w4BMUTPHh6UVSwiPGQ.... woff2 swap
Size 23 KB
Load time 116 ms
Start 1.9 s
Risk FOUT — text flashes from fallback to web font
S6u9w4BMUTPHh6UVSwaPGR_... woff2 swap
Size 5 KB
Load time 122 ms
Start 1.9 s
Risk FOUT — text flashes from fallback to web font
S6uyw4BMUTPHjxAwXjeu.woff2 woff2 swap
Size 6 KB
Load time 126 ms
Start 1.9 s
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+Resource CachingAll resources properly cachedPASS
Resource Caching
All resources properly cached
All resources properly cached
Info::
No caching issues found
All static resources have appropriate caching headers.
A+Critical Rendering PathNo render-blocking resourcesPASS
Critical Rendering Path
No render-blocking resources
No render-blocking resources
Info::
No render-blocking resources detected
A+Resource HintsNo optimization neededPASS
Resource Hints
No optimization needed
No optimization needed
Info::
No resource hint issues
A+HTTP/3 (QUIC)HTTP/3 advertised via Alt-SvcPASS
HTTP/3 (QUIC)
HTTP/3 advertised via Alt-Svc
HTTP/3 advertised via Alt-Svc
Info::
HTTP/3 (QUIC) is supported
First-load mobile users on cellular networks see meaningful latency improvements with HTTP/3. The QUIC transport collapses TLS + TCP handshakes into one and recovers faster from packet loss.
A+LCP Image PreloadLCP preload audit not availablePASS
LCP Image Preload
LCP preload audit not available
LCP preload audit not available
Info::
LCP image preload audit not available for this scan
A+Server Response Intelligence2 server-response signal(s) detectedPASS
Server Response Intelligence
2 server-response signal(s) detected
2 server-response signal(s) detected
Info::
`Vary` header declared: Accept-Encoding
The page declares a `Vary` header, telling downstream caches which request headers the response varies on. Critical for content-negotiated responses (compression, language, cookies, device class).
Info::
No `ETag` or `Last-Modified` -- conditional GET not supported
Without either header, browsers can't issue conditional GETs and refresh always re-downloads the full response body even when nothing changed. Add `ETag: "<hash>"` (or `Last-Modified: <date>`) on cacheable responses; the server returns 304 Not Modified when the client's cached copy is still valid, saving bandwidth.
APage Weight Inventory86 resources · 1.1 MB · 173 KB savings availablePASS
Page Weight Inventory
86 resources · 1.1 MB · 173 KB savings available
86 resources · 1.1 MB · 173 KB savings available
Warning::
Page weight 1.1 MB exceeds 1 MB target by 104 KB
Got: 1.1 MB Expected: ≤ 1 MB
Info::
~173 KB of savings available
Info::
19 third-party resources (36% of weight)
86 resources · 1.1 MiB · 19 third-party 104.5 KiB over 1MB target
JavaScript 45% · 503.6 KiB
Image 42% · 472.6 KiB
Font 6% · 64.1 KiB
Document 4% · 43.8 KiB
CSS 3% · 36.8 KiB
Other 1% · 7.6 KiB
~172.8 KiB of savings available
Remove unused JavaScript: 172.8 KiB
| # | Resource | Type | Size | Cache | Unused | 3rd party | Issues |
|---|---|---|---|---|---|---|---|
| — | — | ||||||
| 86 resources | 1.1 MiB | ||||||
Asset CompressionNo text asset hosts to measureINFO
Asset Compression
No text asset hosts to measure
No text asset hosts to measure
Info::
No third-party or subdomain host served enough text assets to measure
Asset compression is measured per host, from one HEAD request against a sampled resource. Pages that serve all their JS and CSS from the document's own origin are covered by the document compression check instead.
Network Waterfall86 requests over 17816msINFO
Network Waterfall
86 requests over 17816ms
HTML JavaScript CSS Images Fonts XHR/Fetch Other
Third-Party Script CostPer-script blocking time, transfer cost, and cache headersINFO
Third-Party Script Cost
Per-script blocking time, transfer cost, and cache headers
32% of JavaScript execution is third-party
First-party Third-party 226ms · 394KB · ₽118/mo
| Script | Category | Execution | Transfer | Unused | Monthly Cost | Verdict |
|---|---|---|---|---|---|---|
Google Tag Manager www.googletagmanager.com | Tag Manager | 108ms | 189 KB | 38% | ₽56/mo | Costly |
mc.yandex.com mc.yandex.com | Other | 65ms | 69 KB | 53% | ₽34/mo | Optional |
Google Tag Manager www.googletagmanager.com | Tag Manager | 53ms | 136 KB | 48% | ₽28/mo | Optional |
Google Tag Manager
Tag Manager
Execution 108ms
Transfer 189 KB
Unused 38%
Monthly Cost ₽56/mo
mc.yandex.com
Other
Execution 65ms
Transfer 69 KB
Unused 53%
Monthly Cost ₽34/mo
Google Tag Manager
Tag Manager
Execution 53ms
Transfer 136 KB
Unused 48%
Monthly Cost ₽28/mo
These scripts may cost more than they're worth
- Google Tag Manager adds 108ms and costs ~₽56/month
Google Tag Manager takes 108ms of CPU time. Consider loading it asynchronously or replacing it with a lighter alternative.
Why this matters
This script has high main-thread execution time — optimize hot paths or defer.
Source: web.dev
53% of mc.yandex.com's code is unused. The script may be loading features you don't use.
Why this matters
Bundle has high unused-code ratio — tree-shaking and route-splitting recover the wasted bytes.
Source: web.dev
Real-User Performance (CrUX)Field metrics from the Chrome User Experience ReportINFO
Real-User Performance (CrUX)
Field metrics from the Chrome User Experience Report
Chrome User Experience (CrUX)
Real-user metrics from the Chrome UX Report (2026-09-21 — 2026-10-18)
LCP (p75)
2028 ms
80% good
INP (p75)
120 ms
92% good
CLS (p75)
0.000
99% good
FCP (p75)
1901 ms
TTFB (p75)
1887 ms
This origin passes Core Web Vitals assessment
Image Optimization48 images, 184 KB total, 13 KB wastedINFO
Image Optimization
48 images, 184 KB total, 13 KB wasted
Image Optimization Audit
Total Images
48
Total Size
184 KB
Oversized
4
Wasted
13 KB
1 missing lazy loading
All checks on this page are automated. Results are estimates - run targeted manual reviews when the score affects a release decision.