https://master-220v.ru
Performance
· 23 checks — Lighthouse + waterfall + sustainability rolled into one auditable list.SCORE
85
GRADE
B
FIX
2
REVIEW
9
PASS
8
INFO
4
Performance-focused optimization plan with CWV assessment, top offenders, and time estimates
87
71
92
100
First Contentful Paint First Contentful Paint — how long until the browser renders the first piece of content. Under 1.8s is good.
803 ms
Largest Contentful Paint Largest Contentful Paint — how long until the largest visible element loads. Under 2.5s is good.
1.28 s
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.
0.182
Speed Index Speed Index — how quickly content is visually displayed during load. Under 3.4s is good.
1.16 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.
1.28 s
Page Load Progression
1.3 s 2.6 s 3.9 s
5.2 s
6.5 s 7.8 s 9.1 s
10.4 sChecks
238 PASS 9 REVIEW 2 FIX
DPage Weight BudgetAction2.4 MB transferred, 71 requestsFIX
Page Weight Budget
Action2.4 MB transferred, 71 requests
2.4 MB transferred, 71 requests
Info::
Page weighs 3.1 MB (2.4 MB transferred)
Warning::
Images are 1.9 MB — compress or use modern formats
Convert images to WebP/AVIF and resize to display dimensions to reduce transfer size.
Got: 1.9 MB
Info::
71 HTTP requests
Info::
Estimated 0.50 g CO2 per page load
2.4 MB transferred
71 requests
0.50 g CO2 per page load
Images 1.9 MiB 79%
JavaScript 382.1 KiB 16%
Fonts 102.2 KiB 4%
Other 15.6 KiB 1%
HTML 15.2 KiB 1%
Other 3.4 KiB 0%
CSS 2.9 KiB 0%
0 2.4 MB 4.9 MB
Approaching limit
Convert images to WebP/AVIF and resize to display dimensions to reduce transfer size.
Why this matters
Image bandwidth is high — modern formats (WebP/AVIF) and resizing typically cut it 50%+.
Source: web.dev
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.
BImage Optimization47 images, 0 KB saveableREVIEW
Image Optimization
47 images, 0 KB saveable
47 images, 0 KB saveable
Info::
All images are well-optimized
47 images 1.9 MB
0 oversized -0 KB
41 legacy format
0 missing dimensions CLS risk
BJS Execution Cost539ms total JS executionREVIEW
JS Execution Cost
539ms total JS execution
539ms total JS execution
Info::
https://master-220v.ru/: 179ms CPU time
Info::
https://master-220v.ru/slider/js/jquery.min.js: 156ms CPU time
Info::
https://mc.yandex.ru/metrika/tag.js: 69ms CPU time
Info::
Unattributable: 68ms CPU time
Info::
https://www.googletagmanager.com/gtag/js?id=G-XPJ7...: 67ms CPU time
Info::
Third-party scripts: 137ms (25% of total)
Main Thread Breakdown
Script Evaluation 33% Rendering 26% Other 25% Style & Layout 11% Script Parsing & Compilation 4%
| Script | Total | Scripting | Parse/Compile | Party |
|---|---|---|---|---|
| https://master-220v.ru/ | 179ms | 2ms | 1ms | 1st |
| https://master-220v.ru/slider/js/jquery.min.js | 156ms | 56ms | 6ms | 1st |
| https://mc.yandex.ru/metrika/tag.js | 69ms | 58ms | 6ms | 3rd |
| Unattributable | 68ms | 5ms | 0ms | 1st |
| https://www.googletagmanager.com/gtag/js?id=G-XPJ7MLEPWX | 67ms | 56ms | 10ms | 3rd |
CJS BundlesAction4 scripts, 178 KB unusedREVIEW
JS Bundles
Action4 scripts, 178 KB unused
4 scripts, 178 KB unused
Warning::
https://www.googletagmanager.com/gtag/js?id=G-XPJ7...: 73 KB unused (42%)
Consider code splitting or tree shaking to reduce unused code.
Warning::
https://mc.yandex.ru/metrika/tag.js: 53 KB unused (59%)
Consider code splitting or tree shaking to reduce unused code.
Warning::
https://mc.yandex.ru/metrika/tag.js: 53 KB unused (59%)
Consider code splitting or tree shaking to reduce unused code.
Info::
Total unused JavaScript: 178 KB
178 KB unused JavaScript
Downloaded but never executed on this page.
| Script | Size | Unused | Minified | Party |
|---|---|---|---|---|
| https://www.googletagmanager.com/gtag/js?id=G-XPJ7MLEPWX | 173 KB | 73 KB (42%) | ✓ | 3rd |
| https://mc.yandex.ru/metrika/tag.js | 90 KB | 53 KB (59%) | ✓ | 3rd |
| https://mc.yandex.ru/metrika/tag.js | 90 KB | 53 KB (59%) | ✓ | 3rd |
| https://master-220v.ru/slider/js/jquery.min.js | 30 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
BHTTP/3 (QUIC)HTTP/3 not advertisedREVIEW
HTTP/3 (QUIC)
HTTP/3 not advertised
HTTP/3 not advertised
Info::
HTTP/3 (QUIC) is not advertised
HTTP/3 isn't advertised via Alt-Svc and the worker didn't negotiate h3. HTTP/3 reduces handshake latency (1-RTT instead of 2-3 RTTs) and is more resilient on lossy connections. Most modern CDNs (Cloudflare, Fastly, AWS CloudFront, Google Cloud CDN) support HTTP/3 with a single config switch -- consider enabling for mobile-heavy workloads.
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.
CPage Weight InventoryAction71 resources · 2.4 MB · 178 KB savings availableREVIEW
Page Weight Inventory
Action71 resources · 2.4 MB · 178 KB savings available
71 resources · 2.4 MB · 178 KB savings available
Warning::
Page weight 2.4 MB exceeds 1 MB target by 1.4 MB
Got: 2.4 MB Expected: ≤ 1 MB
Info::
~178 KB of savings available
Info::
32 third-party resources (20% of weight)
71 resources · 2.4 MiB · 32 third-party 1.4 MiB over 1MB target
Image 79% · 1.9 MiB
JavaScript 16% · 382.1 KiB
Font 4% · 102.2 KiB
Document 1% · 15.3 KiB
Other 0% · 9.7 KiB
CSS 0% · 2.9 KiB
~178.0 KiB of savings available
Remove unused JavaScript: 178.0 KiB
| # | Resource | Type | Size | Cache | Unused | 3rd party | Issues |
|---|---|---|---|---|---|---|---|
| — | — | ||||||
| 71 resources | 2.4 MiB | ||||||
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
A+Third-Party Impact20% third-party, 0 ms blockingPASS
Third-Party Impact
20% third-party, 0 ms blocking
20% third-party, 0 ms blocking
Info::
Third-party code accounts for 20% of page weight (485.7 KiB of 2.4 MiB)
Info::
Third-party blocking time is low (0 ms)
80%
20%
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 Loading2 fonts (102 KB)PASS
Font Loading
2 fonts (102 KB)
2 fonts (102 KB)
Info::
2 font(s) use font-display: swap (FOUT risk but functional)
Web fonts
2
102 KB total
Render-blocking
0
of 2
Dominant font-display
swap
Most common across fonts
Font loading timeline
Transfer FOIT (block) FOUT (swap)
SmqPmIMEXrW4lOY8QrhTUVD... woff swap
Size 52 KB
Load time 172 ms
Start 816 ms
Risk FOUT — text flashes from fallback to web font
- Convert to woff2 for ~30% smaller file size
bIx8jOfCEfR-mECoDUEZywD... woff swap
Size 50 KB
Load time 142 ms
Start 817 ms
Risk FOUT — text flashes from fallback to web font
- Convert to woff2 for ~30% smaller file size
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)
Fixing the unchecked items could save ~31 KB and ~62 ms
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+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.
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 Waterfall71 requests over 8122msINFO
Network Waterfall
71 requests over 8122ms
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
25% of JavaScript execution is third-party
First-party Third-party 137ms · 263KB · ₽40/mo
| Script | Category | Execution | Transfer | Unused | Monthly Cost | Verdict |
|---|---|---|---|---|---|---|
mc.yandex.ru mc.yandex.ru | Other | 69ms | 90 KB | 59% | ₽21/mo | Optional |
Google Tag Manager www.googletagmanager.com | Tag Manager | 67ms | 173 KB | 42% | ₽20/mo | Optional |
mc.yandex.ru
Other
Execution 69ms
Transfer 90 KB
Unused 59%
Monthly Cost ₽21/mo
Google Tag Manager
Tag Manager
Execution 67ms
Transfer 173 KB
Unused 42%
Monthly Cost ₽20/mo
59% of mc.yandex.ru'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
Image Optimization46 images, 2050 KB total, 0 KB wastedINFO
Image Optimization
46 images, 2050 KB total, 0 KB wasted
Image Optimization Audit
Total Images
46
Total Size
2050 KB
1 missing dimensions 40 missing lazy loading
All checks on this page are automated. Results are estimates - run targeted manual reviews when the score affects a release decision.