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
Image Optimization
Action
21 images, 0 KB saveable
REVIEW
21 images, 0 KB saveable
Warning::
!
https://cdn.prod.website-files.com/64394b14f51ad18... is missing width/height — may cause layout shift
Set explicit width and height to prevent CLS.
Warning::
!
https://cdn.prod.website-files.com/64394b14f51ad18... is missing width/height — may cause layout shift
Set explicit width and height to prevent CLS.
Warning::
!
https://cdn.prod.website-files.com/6140ca4a71c3bf5... is missing width/height — may cause layout shift
Set explicit width and height to prevent CLS.
Warning::
!
https://cdn.prod.website-files.com/64394b14f51ad18... is missing width/height — may cause layout shift
Set explicit width and height to prevent CLS.
Warning::
!
https://cdn.prod.website-files.com/64394b14f51ad18... is missing width/height — may cause layout shift
Set explicit width and height to prevent CLS.
21images617 KB
0oversized-0 KB
17legacy format
5missing dimensionsCLS 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
B
Document Compression
Document response uses gzip; brotli would be ~20% smaller
REVIEW
Document response uses gzip; brotli would be ~20% smaller
Info::
i
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::
i
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::
i
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
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 5.3 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.
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
42 fonts (1106 KB)
PASS
42 fonts (1106 KB)
Info::
i
42 font(s) use font-display: swap (FOUT risk but functional)
Web fonts
42
1106 KB total
Render-blocking
0
of 42
Dominant font-display
swap
Most common across fonts
Font loading timeline
TransferFOIT (block)FOUT (swap)
x-font-ttf;charset=utf-...unknownswap
Size2 KB
Load time25 ms
Start263 ms
RiskFOUT — text flashes from fallback to web font
lwoff2swap
Size24 KB
Load time11 ms
Start297 ms
RiskFOUT — text flashes from fallback to web font
lwoff2swap
Size24 KB
Load time11 ms
Start297 ms
RiskFOUT — text flashes from fallback to web font
lwoff2swap
Size32 KB
Load time13 ms
Start298 ms
RiskFOUT — text flashes from fallback to web font
SlGVmQWMvZQIdix7AFxXkHN...woff2swap
Size11 KB
Load time44 ms
Start397 ms
RiskFOUT — text flashes from fallback to web font
SlGWmQWMvZQIdix7AFxXmMh...woff2swap
Size11 KB
Load time104 ms
Start398 ms
RiskFOUT — text flashes from fallback to web font
memvYaGs126MiZpBA-UvWbX...woff2swap
Size42 KB
Load time123 ms
Start398 ms
RiskFOUT — text flashes from fallback to web font
memtYaGs126MiZpBA-UFUIc...woff2swap
Size44 KB
Load time124 ms
Start399 ms
RiskFOUT — text flashes from fallback to web font
jizaRExUiTo99u79D0KExcO...woff2swap
Size11 KB
Load time91 ms
Start399 ms
RiskFOUT — text flashes from fallback to web font
jizYRExUiTo99u79D0e0x8m...woff2swap
Size12 KB
Load time99 ms
Start399 ms
RiskFOUT — text flashes from fallback to web font
jizfRExUiTo99u79B_mh0O6...woff2swap
Size11 KB
Load time64 ms
Start399 ms
RiskFOUT — text flashes from fallback to web font
jizdRExUiTo99u79D0e8fOy...woff2swap
Size12 KB
Load time108 ms
Start399 ms
RiskFOUT — text flashes from fallback to web font
lwoff2swap
Size36 KB
Load time16 ms
Start595 ms
RiskFOUT — text flashes from fallback to web font
lwoff2swap
Size38 KB
Load time16 ms
Start595 ms
RiskFOUT — text flashes from fallback to web font
lwoff2swap
Size45 KB
Load time19 ms
Start595 ms
RiskFOUT — text flashes from fallback to web font
lwoff2swap
Size60 KB
Load time20 ms
Start595 ms
RiskFOUT — text flashes from fallback to web font
lwoff2swap
Size24 KB
Load time20 ms
Start595 ms
RiskFOUT — text flashes from fallback to web font
lwoff2swap
Size24 KB
Load time21 ms
Start595 ms
RiskFOUT — text flashes from fallback to web font
lwoff2swap
Size25 KB
Load time21 ms
Start595 ms
RiskFOUT — text flashes from fallback to web font
lwoff2swap
Size25 KB
Load time22 ms
Start596 ms
RiskFOUT — text flashes from fallback to web font
lwoff2swap
Size23 KB
Load time22 ms
Start596 ms
RiskFOUT — text flashes from fallback to web font
lwoff2swap
Size23 KB
Load time20 ms
Start599 ms
RiskFOUT — text flashes from fallback to web font
lwoff2swap
Size24 KB
Load time20 ms
Start600 ms
RiskFOUT — text flashes from fallback to web font
lwoff2swap
Size24 KB
Load time21 ms
Start600 ms
RiskFOUT — text flashes from fallback to web font
lwoff2swap
Size24 KB
Load time21 ms
Start600 ms
RiskFOUT — text flashes from fallback to web font
lwoff2swap
Size25 KB
Load time21 ms
Start601 ms
RiskFOUT — text flashes from fallback to web font
lwoff2swap
Size18 KB
Load time21 ms
Start601 ms
RiskFOUT — text flashes from fallback to web font
lwoff2swap
Size15 KB
Load time21 ms
Start601 ms
RiskFOUT — text flashes from fallback to web font
lwoff2swap
Size18 KB
Load time21 ms
Start602 ms
RiskFOUT — text flashes from fallback to web font
lwoff2swap
Size19 KB
Load time21 ms
Start603 ms
RiskFOUT — text flashes from fallback to web font
lwoff2swap
Size19 KB
Load time21 ms
Start603 ms
RiskFOUT — text flashes from fallback to web font
lwoff2swap
Size32 KB
Load time22 ms
Start603 ms
RiskFOUT — text flashes from fallback to web font
lwoff2swap
Size33 KB
Load time23 ms
Start603 ms
RiskFOUT — text flashes from fallback to web font
lwoff2swap
Size32 KB
Load time23 ms
Start604 ms
RiskFOUT — text flashes from fallback to web font
lwoff2swap
Size28 KB
Load time24 ms
Start604 ms
RiskFOUT — text flashes from fallback to web font
lwoff2swap
Size27 KB
Load time24 ms
Start604 ms
RiskFOUT — text flashes from fallback to web font
lwoff2swap
Size28 KB
Load time25 ms
Start604 ms
RiskFOUT — text flashes from fallback to web font
lwoff2swap
Size27 KB
Load time27 ms
Start605 ms
RiskFOUT — text flashes from fallback to web font
lwoff2swap
Size31 KB
Load time28 ms
Start605 ms
RiskFOUT — text flashes from fallback to web font
lwoff2swap
Size31 KB
Load time29 ms
Start605 ms
RiskFOUT — text flashes from fallback to web font
memvYaGs126MiZpBA-UvWbX...woff2swap
Size47 KB
Load time68 ms
Start1.3 s
RiskFOUT — text flashes from fallback to web font
open-sans-v17-vietnames...woff2swap
Size43 KB
Load time19 ms
Start3.7 s
RiskFOUT — 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)
Fixing the unchecked items could save ~1 KB and ~2 ms
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
5 hints, 0 missing preconnects
PASS
5 hints, 0 missing preconnects
Info::
✓
Page uses 5 resource hint(s)
Current Resource Hints
preconnect
5
preload—
dns-prefetch—
prefetch—
5 resource hints configured
A+
HTTP/3 (QUIC)
HTTP/3 advertised via Alt-Svc
PASS
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+
Asset Compression
All 1 asset host use brotli
PASS
All 1 asset host use brotli
Info::
✓
cdn.prod.website-files.com serves assets with brotli (assets: 41)
Got: cdn.prod.website-files.com (text/css)
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::
✓
`Last-Modified` present -- timestamp-based conditional GET supported
Consider also setting `ETag` for stronger revalidation -- ETags are content hashes that don't suffer from clock-skew or DST issues. Last-Modified alone is functional for conditional GETs and not a bug.
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
A+
Green Hosting
Whether the site is served from green-energy infrastructure
PASS
Green Hosting
This site is hosted on green energy infrastructure
Provider: Cloudflare
Network Waterfall
113 requests over 3763ms
INFO
HTML JavaScript CSS Images Fonts XHR/Fetch Other
Third-Party Script Cost
Per-script blocking time, transfer cost, and cache headers
INFO
74%of JavaScript execution is third-party
First-party Third-party3945ms · 945KB · €21/mo
Script
Category
Execution
Transfer
Unused
Monthly Cost
Verdict
universe-static.elfsightcdn.com
universe-static.elfsightcdn.com
Other
2036ms
462 KB
46%
€11/mo
Costly
cdn.prod.website-files.com
cdn.prod.website-files.com
Other
1206ms
26 KB
—
€6/mo
Costly
d3e54v103j8qbb.cloudfront.net
d3e54v103j8qbb.cloudfront.net
Other
146ms
31 KB
—
€1/mo
Optional
static.botsrv2.com
static.botsrv2.com
Other
144ms
24 KB
—
€1/mo
Optional
Google Tag Manager
www.googletagmanager.com
Tag Manager
127ms
178 KB
41%
€1/mo
Optional
Google Tag Manager
www.googletagmanager.com
Tag Manager
121ms
123 KB
52%
€1/mo
Optional
cdn.prod.website-files.com
cdn.prod.website-files.com
Other
92ms
1 KB
—
€0/mo
Optional
cookie.bestfreecdn.com
cookie.bestfreecdn.com
Other
73ms
101 KB
87%
€0/mo
Optional
universe-static.elfsightcdn.com
Other
Costly
Execution2036ms
Transfer462 KB
Unused46%
Monthly Cost€11/mo
cdn.prod.website-files.com
Other
Costly
Execution1206ms
Transfer26 KB
Monthly Cost€6/mo
d3e54v103j8qbb.cloudfront.net
Other
Optional
Execution146ms
Transfer31 KB
Monthly Cost€1/mo
static.botsrv2.com
Other
Optional
Execution144ms
Transfer24 KB
Monthly Cost€1/mo
Google Tag Manager
Tag Manager
Optional
Execution127ms
Transfer178 KB
Unused41%
Monthly Cost€1/mo
Google Tag Manager
Tag Manager
Optional
Execution121ms
Transfer123 KB
Unused52%
Monthly Cost€1/mo
cdn.prod.website-files.com
Other
Optional
Execution92ms
Transfer1 KB
Monthly Cost€0/mo
cookie.bestfreecdn.com
Other
Optional
Execution73ms
Transfer101 KB
Unused87%
Monthly Cost€0/mo
These scripts may cost more than they're worth
universe-static.elfsightcdn.com adds 2036ms and costs ~€11/month
cdn.prod.website-files.com adds 1206ms and costs ~€6/month
74% of JavaScript execution time is spent on third-party scripts. Consider auditing which scripts are essential.
Why this matters
When third-party JS execution time exceeds your own, performance gains from frontend work are capped by code you don't own.
Learn more ▾▴
Every millisecond of third-party JS competes with your own for main-thread time. If their share is bigger than yours, optimization on your code base barely moves the needle. Audit, defer, or remove third-parties before further frontend optimization. Use Lighthouse's third-party audit to identify the worst offenders.
Source: web.dev
universe-static.elfsightcdn.com takes 2036ms 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
cdn.prod.website-files.com takes 1206ms 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
52% of Google Tag Manager'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
87% of cookie.bestfreecdn.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.