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.
B
Image Optimization
22 images, 0 KB saveable
REVIEW
22 images, 0 KB saveable
Warning::
!
https://static.rollercoin.com/static/img/ref/gen2/... is missing width/height — may cause layout shift
Set explicit width and height to prevent CLS.
22images986 KB
0oversized-0 KB
20legacy format
1missing 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
B
HTTP/3 (QUIC)
HTTP/3 not advertised
REVIEW
HTTP/3 not advertised
Info::
i
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
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
JavaScript Blocking
1 JS blocking issue(s) detected
REVIEW
1 JS blocking issue(s) detected
Warning::
!
12 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.
C
Green Hosting
Action
Whether the site is served from green-energy infrastructure
REVIEW
Green Hosting
No green hosting detected
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
6 fonts (558 KB)
PASS
6 fonts (558 KB)
Info::
i
6 font(s) use font-display: swap (FOUT risk but functional)
Web fonts
6
558 KB total
Render-blocking
0
of 6
Dominant font-display
swap
Most common across fonts
Font loading timeline
TransferFOIT (block)FOUT (swap)
woff2;base64,d09GMgABAA...woff2swap
Size9 KB
Load time36 ms
Start611 ms
RiskFOUT — text flashes from fallback to web font
cousine_normal_400.ttfttfswap
Size163 KB
Load time29 ms
Start644 ms
RiskFOUT — text flashes from fallback to web font
Convert to woff2 for ~30% smaller file size
Subset this font — over 100 KB suggests Latin Extended or full glyph coverage that most pages don't need
pixeloid-sans_normal_70...otfswap
Size37 KB
Load time9 ms
Start645 ms
RiskFOUT — text flashes from fallback to web font
Convert to woff2 for ~30% smaller file size
cousine_italic_400.ttfttfswap
Size151 KB
Load time28 ms
Start647 ms
RiskFOUT — text flashes from fallback to web font
Convert to woff2 for ~30% smaller file size
Subset this font — over 100 KB suggests Latin Extended or full glyph coverage that most pages don't need
pixeloid-sans_normal_40...otfswap
Size40 KB
Load time11 ms
Start647 ms
RiskFOUT — text flashes from fallback to web font
Convert to woff2 for ~30% smaller file size
cousine_normal_700.ttfttfswap
Size158 KB
Load time24 ms
Start647 ms
RiskFOUT — text flashes from fallback to web font
Convert to woff2 for ~30% smaller file size
Subset this font — over 100 KB suggests Latin Extended or full glyph coverage that most pages don't need
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 ~401 KB and ~802 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
6 hints, 0 missing preconnects
PASS
6 hints, 0 missing preconnects
Info::
✓
Page uses 6 resource hint(s)
Current Resource Hints
preconnect—
preload
3
dns-prefetch
3
prefetch—
6 resource hints configured
A+
Document Compression
Document response uses brotli
PASS
Document response uses brotli
Info::
✓
Main HTML response uses brotli (Content-Encoding: br)
Brotli is the best text-compression algorithm for general use, ~20% smaller than gzip on average (40% on smaller files). Modern browsers all support it.
A+
Asset Compression
All 1 asset host use brotli
PASS
All 1 asset host use brotli
Info::
✓
0.gravatar.com serves assets with brotli (assets: 4)
Got: 0.gravatar.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-Timing Observability
3 Server-Timing entries advertised
PASS
3 Server-Timing entries advertised
Info::
✓
Server-Timing header advertises 3 timing entries
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::
i
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.
Each `<link rel="stylesheet">` without a non-blocking `media` attribute holds up the first paint. Browsers download all of them before painting any content. Consolidate into 1-2 critical-path stylesheets; defer non-critical CSS via `<link rel="stylesheet" media="print" onload="this.media='all'">` or via the loadCSS pattern; inline above-the-fold CSS in `<style>` to short-circuit the request entirely.
Network Waterfall
86 requests over 1929ms
INFO
HTML JavaScript CSS Images Fonts XHR/Fetch Other
Third-Party Script Cost
Per-script blocking time, transfer cost, and cache headers
INFO
46%of JavaScript execution is third-party
First-party Third-party1194ms · 752KB · $16/mo
Script
Category
Execution
Transfer
Unused
Monthly Cost
Verdict
dn0qt3r0xannq.cloudfront.net
dn0qt3r0xannq.cloudfront.net
Other
255ms
118 KB
52%
$3/mo
Costly
edge.aditude.io
edge.aditude.io
Other
220ms
161 KB
76%
$3/mo
Costly
securepubads.g.doubleclick.net
securepubads.g.doubleclick.net
Other
180ms
210 KB
75%
$2/mo
Optional
c.amazon-adsystem.com
c.amazon-adsystem.com
Other
154ms
95 KB
58%
$2/mo
Optional
raven-static.aditude.io
raven-static.aditude.io
Other
138ms
105 KB
61%
$2/mo
Optional
s0.wp.com
s0.wp.com
Other
108ms
8 KB
—
$1/mo
Optional
securepubads.g.doubleclick.net
securepubads.g.doubleclick.net
Other
84ms
38 KB
—
$1/mo
Optional
Google Analytics
ssl.google-analytics.com
Analytics
55ms
17 KB
—
$1/mo
Optional
dn0qt3r0xannq.cloudfront.net
Other
Costly
Execution255ms
Transfer118 KB
Unused52%
Monthly Cost$3/mo
edge.aditude.io
Other
Costly
Execution220ms
Transfer161 KB
Unused76%
Monthly Cost$3/mo
securepubads.g.doubleclick.net
Other
Optional
Execution180ms
Transfer210 KB
Unused75%
Monthly Cost$2/mo
c.amazon-adsystem.com
Other
Optional
Execution154ms
Transfer95 KB
Unused58%
Monthly Cost$2/mo
raven-static.aditude.io
Other
Optional
Execution138ms
Transfer105 KB
Unused61%
Monthly Cost$2/mo
s0.wp.com
Other
Optional
Execution108ms
Transfer8 KB
Monthly Cost$1/mo
securepubads.g.doubleclick.net
Other
Optional
Execution84ms
Transfer38 KB
Monthly Cost$1/mo
Google Analytics
Analytics
Optional
Execution55ms
Transfer17 KB
Monthly Cost$1/mo
These scripts may cost more than they're worth
dn0qt3r0xannq.cloudfront.net adds 255ms and costs ~$3/month
edge.aditude.io adds 220ms and costs ~$3/month
46% of JavaScript execution time comes from third-party scripts.
Why this matters
Third-party scripts (analytics, ads, social, A/B testing) often dominate execution time — every one is a perf-and-privacy tax.
Learn more ▾▴
Each third-party script is a black box: you don't control when it loads, what it executes, or how much it grows. They often account for a major share of total blocking time on average sites (HTTP Archive's Web Almanac documents the trend). Audit which ones you actually need, defer the rest, and use facade patterns (lite-youtube, lite-vimeo) for embedded media.
Source: web.dev / HTTP Archive Web Almanac
dn0qt3r0xannq.cloudfront.net takes 255ms 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 dn0qt3r0xannq.cloudfront.net'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
edge.aditude.io takes 220ms 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
76% of edge.aditude.io'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
75% of securepubads.g.doubleclick.net'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
58% of c.amazon-adsystem.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
61% of raven-static.aditude.io'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.