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https://bestref.net

Performance

· 26 checks — Lighthouse + waterfall + sustainability rolled into one auditable list.
SCORE
87
GRADE
B
FIX
2
REVIEW
9
PASS
12
INFO
3

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

Mobile Desktop
57
Performance Overall performance score (0–100) based on Core Web Vitals and other metrics. 90+ is good.
92
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.

3.09 s

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

3.92 s

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

264 ms

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

0.213

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

18.15 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.

5.45 s

Page Load Progression

1.5 s
3.0 s
4.6 s
6.1 s
7.6 s
9.1 s
10.6 s
12.1 s
Checks
26
12 PASS 9 REVIEW 2 FIX
F
JS Execution Cost
Action
8310ms total JS execution
FIX
8310ms total JS execution
Warning::
https://bestref.net/: 7844ms CPU time
Warning::
Unattributable: 331ms CPU time
Info::
https://code.jquery.com/jquery-3.5.1.min.js: 135ms CPU time
Info::
Third-party scripts: 135ms (2% of total)

Main Thread Breakdown

Style & Layout 41% Rendering 33% Other 24%
ScriptTotalScriptingParse/CompileParty
https://bestref.net/7844ms5ms1ms1st
Unattributable331ms6ms0ms1st
https://code.jquery.com/jquery-3.5.1.min.js135ms85ms21ms3rd
D
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::
ETag present — enables conditional (304) responses
Info::
Last-Modified header present

No Cache-Control header

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

B
Page Weight Budget
1.2 MB transferred, 27 requests
REVIEW
1.2 MB transferred, 27 requests
Info::
Page weighs 1.6 MB (1.2 MB transferred)
Warning::
Images are 1.1 MB — compress or use modern formats
Convert images to WebP/AVIF and resize to display dimensions to reduce transfer size.
Got: 1.1 MB
Info::
27 HTTP requests
Info::
Estimated 0.26 g CO2 per page load
1.2 MB / 2.4 MB budget
1.2 MB transferred
27 requests
0.26 g CO2 per page load
Images 1.1 MiB 92%
JavaScript 41.5 KiB 3%
Fonts 34.7 KiB 3%
CSS 12.4 KiB 1%
HTML 10.0 KiB 1%
Other 1.1 KiB 0%
0 2.4 MB 4.9 MB
Under budget

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

C
Image Optimization
Action
17 images, 0 KB saveable
REVIEW
17 images, 0 KB saveable
Warning::
https://bestref.net/images/popup-close.png is missing width/height — may cause layout shift
Set explicit width and height to prevent CLS.
Warning::
https://bestref.net/images/btn-lock.png is missing width/height — may cause layout shift
Set explicit width and height to prevent CLS.
Warning::
https://bestref.net/images/new-arrow.png is missing width/height — may cause layout shift
Set explicit width and height to prevent CLS.
Warning::
https://bestref.net/images/popup-facebook-icon.png is missing width/height — may cause layout shift
Set explicit width and height to prevent CLS.
Warning::
https://bestref.net/images/popup-google-icon.png is missing width/height — may cause layout shift
Set explicit width and height to prevent CLS.
Warning::
https://bestref.net/images/main-logo.png is missing width/height — may cause layout shift
Set explicit width and height to prevent CLS.
Warning::
https://bestref.net/images/footer-twitter.png is missing width/height — may cause layout shift
Set explicit width and height to prevent CLS.
Warning::
https://bestref.net/images/footer-toTop.png is missing width/height — may cause layout shift
Set explicit width and height to prevent CLS.
17 images 1.1 MB
0 oversized -0 KB
17 legacy format
8 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

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

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
HTTP/3 (QUIC)
HTTP/3 not advertised
REVIEW
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.
B
Compression Algorithm
Main response uses gzip; brotli would be ~20% smaller
REVIEW
Main 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.
B
Main HTML Cache-Control
No Cache-Control header on main HTML response
REVIEW
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.
B
Server-Timing Observability
No Server-Timing header found
REVIEW
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.
B
Page Weight Inventory
27 resources · 1.2 MB · 21 KB savings available
REVIEW
27 resources · 1.2 MB · 21 KB savings available
Warning::
Page weight 1.2 MB exceeds 1 MB target by 234 KB
Got: 1.2 MB Expected: ≤ 1 MB
Info::
3 third-party resources (5% of weight)
Info::
2 resources over 200KB
27 resources · 1.2 MiB · 3 third-party 233.8 KiB over 1MB target
Image 92% · 1.1 MiB
JavaScript 3% · 41.5 KiB
Font 3% · 34.7 KiB
CSS 1% · 12.4 KiB
Document 1% · 10.0 KiB

~21.3 KiB of savings available

Remove unused JavaScript: 21.3 KiB
B
JavaScript Blocking
2 JS blocking issue(s) detected
REVIEW
2 JS blocking issue(s) detected
Warning::
3 render-blocking <script src> tag(s) without async/defer
Each `<script src=...>` without `async`, `defer`, or `type="module"` blocks HTML parsing while the browser fetches and executes it. The block lasts the entire round-trip + execution time -- on slow networks this translates directly into LCP delay. Add `defer` (executes after parse, in source order) for scripts that interact with the DOM, or `async` (executes whenever ready) for analytics / independent scripts. Module scripts (`type="module"`) are deferred by default.
Warning::
Total JS execution time is 8.3 s -- over the 3.5s budget
Total JavaScript execution (parse + compile + run) across all scripts exceeds 3.5 seconds. On low-end devices that becomes 7-15+ seconds and shows up directly in TBT and INP. Reduce by: tree-shaking unused dependencies, code-splitting (dynamic `import()`), removing or deferring third-party tracking, and replacing heavy frameworks where they're not needed.
C
Green Hosting
Action
Whether the site is served from green-energy infrastructure
REVIEW

Green Hosting

No green hosting detected

A+
Third-Party Impact
5% third-party, 0 ms blocking
PASS
5% third-party, 0 ms blocking
Info::
Third-party code accounts for 5% of page weight (66.7 KiB of 1.2 MiB)
Info::
Third-party blocking time is low (0 ms)
95%
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+
Font Loading
1 fonts (35 KB)
PASS
1 fonts (35 KB)
Info::
1 font(s) use font-display: swap (FOUT risk but functional)

Web fonts

1

35 KB total

Render-blocking

0

of 1

Dominant font-display

swap

Most common across fonts

Font loading timeline
Transfer FOIT (block) FOUT (swap)
0 ms 2.0 s 4.0 s 6.0 s 8.0 s 10.0 s 12.0 s FCP 3.1 s LCP 3.9 shttps://fonts.gstatic.com/s/montserrat/v31/JTUSjIg1_i6t8kCHKm459WlhyyTh89Y.woff2JTUSjIg1_i6t8kCHKm459Wl... https://fonts.gstatic.com/s/montserrat/v31/JTUSjIg1_i6t8kCHKm459WlhyyTh89Y.woff2 — 34.7 KiB — 17 ms — font-display: swap
JTUSjIg1_i6t8kCHKm459Wl... woff2 swap
Size 35 KB
Load time 17 ms
Start 11.5 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+
JS Bundles
3 scripts, 21 KB unused
PASS
3 scripts, 21 KB unused
Warning::
https://code.jquery.com/jquery-3.5.1.min.js: 21 KB unused (71%)
Consider code splitting or tree shaking to reduce unused code.
Info::
Total unused JavaScript: 21 KB
21 KB unused JavaScript

Downloaded but never executed on this page.

ScriptSizeUnusedMinifiedParty
https://code.jquery.com/jquery-3.5.1.min.js31 KB21 KB (71%)✓3rd
https://bestref.net/js/slick.min.js10 KB—✓1st
https://bestref.net/js/scripts.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

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+
LCP Image Preload
LCP preload audit not available
PASS
LCP preload audit not available
Info::
LCP image preload audit not available for this scan
A+
Server Response Intelligence
2 server-response signal(s) detected
PASS
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::
Both `ETag` and `Last-Modified` present -- efficient revalidation supported
The page returns both `ETag` (content hash) and `Last-Modified` (timestamp) headers. Browsers can issue conditional GETs with `If-None-Match` or `If-Modified-Since`; the server returns 304 Not Modified for unchanged content, saving bandwidth. ETag is the more reliable of the two (timestamps fail in DST transitions and clock skew).
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
A+
CSS Performance Depth
No CSS performance depth issues detected
PASS
No CSS performance depth issues detected
Info::
No CSS performance depth issues detected
Network Waterfall
27 requests over 12156ms
INFO
0 ms 2.0 s 4.0 s 6.0 s 8.0 s 10.0 s 12.0 s FCP 3.1 s LCP 3.9 shttps://bestref.net// https://bestref.net/ — 200 — 10.0 KiB — 11.0 s — h2https://fonts.googleapis.com/css?family=Montserrat:100,100italic,200,200italic,300,300italic,500,500italic,900italic,900,800italic,800,700italic,700,600italic,600&subset=latin-extfonts.googleapis.com/css?family=Mon... https://fonts.googleapis.com/css?family=Montserrat:100,100italic,200,200italic,300,300italic,500,500italic,900italic,900,800italic,800,700italic,700,600italic,600&subset=latin-ext — 200 — 1.5 KiB — 150 ms — h2https://bestref.net/css/style.css?ver=1.03/css/style.css?ver=1.03 https://bestref.net/css/style.css?ver=1.03 — 200 — 7.5 KiB — 156 ms — h2https://bestref.net/css/style2.css/css/style2.css https://bestref.net/css/style2.css — 200 — 3.4 KiB — 158 ms — h2https://bestref.net/images/btn-lock.png/images/btn-lock.png https://bestref.net/images/btn-lock.png — 200 — 2.6 KiB — 164 ms — h2https://bestref.net/images/popup-close.png/images/popup-close.png https://bestref.net/images/popup-close.png — 200 — 488 B — 167 ms — h2https://code.jquery.com/jquery-3.5.1.min.jscode.jquery.com/jquery-3.5.1.min.js https://code.jquery.com/jquery-3.5.1.min.js — 200 — 30.5 KiB — 37 ms — h2https://bestref.net/js/slick.min.js/js/slick.min.js https://bestref.net/js/slick.min.js — 200 — 10.4 KiB — 287 ms — h2https://bestref.net/js/scripts.js/js/scripts.js https://bestref.net/js/scripts.js — 200 — 589 B — 287 ms — h2https://bestref.net/images/popup-facebook-icon.png/images/popup-facebook-icon.png https://bestref.net/images/popup-facebook-icon.png — 200 — 796 B — 293 ms — h2https://bestref.net/images/popup-google-icon.png/images/popup-google-icon.png https://bestref.net/images/popup-google-icon.png — 200 — 1.1 KiB — 297 ms — h2https://bestref.net/images/main-logo.png/images/main-logo.png https://bestref.net/images/main-logo.png — 200 — 132.4 KiB — 432 ms — h2https://bestref.net/images/new-arrow.png/images/new-arrow.png https://bestref.net/images/new-arrow.png — 200 — 366 B — 430 ms — h2https://bestref.net/images/footer-twitter.png/images/footer-twitter.png https://bestref.net/images/footer-twitter.png — 200 — 690 B — 430 ms — h2https://bestref.net/images/footer-toTop.png/images/footer-toTop.png https://bestref.net/images/footer-toTop.png — 200 — 1.8 KiB — 430 ms — h2https://bestref.net/images/main-bg01.jpg/images/main-bg01.jpg https://bestref.net/images/main-bg01.jpg — 200 — 669.9 KiB — 692 ms — h2https://bestref.net/images/log-bg.png/images/log-bg.png https://bestref.net/images/log-bg.png — 200 — 9.9 KiB — 430 ms — h2https://bestref.net/images/sign-bg.png/images/sign-bg.png https://bestref.net/images/sign-bg.png — 200 — 9.0 KiB — 430 ms — h2https://bestref.net/images/popup-bg.png/images/popup-bg.png https://bestref.net/images/popup-bg.png — 200 — 15.3 KiB — 431 ms — h2https://bestref.net/images/popup-facebook.png/images/popup-facebook.png https://bestref.net/images/popup-facebook.png — 200 — 32.4 KiB — 432 ms — h2https://bestref.net/images/popup-google.png/images/popup-google.png https://bestref.net/images/popup-google.png — 200 — 25.1 KiB — 536 ms — h2https://bestref.net/images/popup-btn.png/images/popup-btn.png https://bestref.net/images/popup-btn.png — 200 — 9.0 KiB — 531 ms — h2https://bestref.net/images/media-bg.png/images/media-bg.png https://bestref.net/images/media-bg.png — 200 — 225.4 KiB — 686 ms — h2https://bestref.net/images/footer-bg.jpg/images/footer-bg.jpg https://bestref.net/images/footer-bg.jpg — 200 — 22.0 KiB — 481 ms — h2https://fonts.gstatic.com/s/montserrat/v31/JTUSjIg1_i6t8kCHKm459WlhyyTh89Y.woff2fonts.gstatic.com/s/montserrat/v31/... https://fonts.gstatic.com/s/montserrat/v31/JTUSjIg1_i6t8kCHKm459WlhyyTh89Y.woff2 — 200 — 34.7 KiB — 17 ms — h3https://bestref.net/favicon.ico/favicon.ico https://bestref.net/favicon.ico — 200 — 1.1 KiB — 147 ms — h2https://bestref.net/favicon.ico/favicon.ico https://bestref.net/favicon.ico — 200 — 0 B — 12 ms — h2
HTML JavaScript CSS Images Fonts XHR/Fetch Other
Third-Party Script Cost
Per-script blocking time, transfer cost, and cache headers
INFO
2% of JavaScript execution is third-party
First-party Third-party 135ms · 31KB · €1/mo
code.jquery.com
Other
Optional
Execution 135ms
Transfer 31 KB
Unused 71%
Monthly Cost €1/mo

71% of code.jquery.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

How third-party costs are calculated

Image Optimization
11 images, 146 KB total, 0 KB wasted
INFO

Image Optimization Audit

Total Images

11

Total Size

146 KB

11 missing dimensions 5 missing lazy loading
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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