Performance

· 24 checks — Lighthouse + waterfall + sustainability rolled into one auditable list.

SCORE

GRADE

FIX

REVIEW

PASS

INFO

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

Mobile Desktop

Performance

Accessibility

100

Best Practices

100

SEO

First Contentful Paint First Contentful Paint — how long until the browser renders the first piece of content. Under 1.8s is good.

796 ms

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

1.37 s

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

6 ms

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

0.000

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

1.41 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.

2.47 s

Page Load Progression

502 ms

1.0 s

1.5 s

2.0 s

2.5 s

3.0 s

3.5 s

4.0 s

Checks

11 PASS 7 REVIEW 1 FIX

Page Weight Budget

Action

4.9 MB transferred, 50 requests

FIX

4.9 MB transferred, 50 requests

Page weighs 7.1 MB (4.9 MB transferred)

Images are 1.7 MB — compress or use modern formats

Convert images to WebP/AVIF and resize to display dimensions to reduce transfer size.

Got: 1.7 MB

JavaScript is 773 KB — consider code splitting or lazy loading

Large JavaScript bundles delay interactivity. Split code by route or defer non-critical scripts.

Got: 773 KB

50 HTTP requests

Estimated 1.0 g CO2 per page load

4.9 MB transferred

50 requests

1.0 g CO2 per page load

Other 2.3 MiB 46%

Images 1.7 MiB 34%

JavaScript 772.7 KiB 15%

Other 88.2 KiB 2%

Fonts 73.7 KiB 1%

CSS 14.8 KiB 0%

HTML 13.5 KiB 0%

Other 11.0 KiB 0%

Other 553 B 0%

Other 46 B 0%

0 2.4 MB 4.9 MB

Over 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

Large JavaScript bundles delay interactivity. Split code by route or defer non-critical scripts.

Why this matters

JavaScript bundle is large — code-split routes and lazy-load off-screen components to defer.

Source: web.dev

Image Optimization

10 images, 0 KB saveable

REVIEW

10 images, 0 KB saveable

All images are well-optimized

10 images 1.7 MB

0 oversized -0 KB

9 legacy format

0 missing dimensions CLS risk

JS Bundles

23 scripts, 136 KB unused

REVIEW

23 scripts, 136 KB unused

https://www.googletagmanager.com/gtm.js?id=GTM-N3N...: 75 KB unused (65%)

Consider code splitting or tree shaking to reduce unused code.

https://www.googletagmanager.com/gtag/js?id=G-R22L...: 62 KB unused (31%)

Consider code splitting or tree shaking to reduce unused code.

Total unused JavaScript: 136 KB

136 KB unused JavaScript

Downloaded but never executed on this page.

Script	Size	Unused	Minified	Party
https://www.googletagmanager.com/gtm.js?id=GTM-N3NVVSVB	116 KB	75 KB (65%)	✓	3rd
https://www.googletagmanager.com/gtag/js?id=G-R22LR0L6W2	196 KB	62 KB (31%)	✓	3rd
https://maps.gstatic.com/maps-api-v3/embed/js/66/13d/init_embed.js	74 KB	—	✓	3rd
https://maps.googleapis.com/maps-api-v3/api/js/66/13d/geometry.js	3 KB	—	✓	3rd
https://vitalitydentistry.com/cookie-consent.js?v=2	3 KB	—	✓	1st
https://vitalitydentistry.com/search.js	6 KB	—	✓	1st
https://vitalitydentistry.com/analytics.js?v=5	2 KB	—	✓	1st
https://vitalitydentistry.com/airo-logo-orientation.js	2 KB	—	✓	1st
https://plausible.io/js/script.js	2 KB	—	✓	3rd
https://googleads.g.doubleclick.net/pagead/viewthroughconversion/18482887555/?random=1794454092486&cv=11&fst=1794454092486&bg=ffffff&guid=ON&async=1&en=gtag.config&gtm=45je6ba1v9265598231za208zd9265598231xecxf1&gcd=13l3l3l3l1l1&dma=0&tag_exp=115616986~115938465~115938469~118897920~118897930~119863601~120213116~120385423~120412526~120420416~120469145~120469153~121191153~121246026~121246034~123329123~124025272~124170881&u_w=800&u_h=600&url=https%3A%2F%2Fvitalitydentistry.com%2F&rcb=1&frm=0&tiba=Dentistry%20at%20Vitality%20Health%20%7C%20Markham%20Dentist%20Since%201985&hn=www.googleadservices.com&npa=0&pscdl=noapi&auid=1075216548.1794454092&uaa=x86&uab=64&uafvl=Not%253AA-Brand%3B8.0.0.0%7CChromium%3B156.0.8078.79&uamb=0&uam=&uap=macOS&uapv=10.15.7&uaw=0&data=event%3Dgtag.config&ept=9&rfmt=3&fmt=4	3 KB	—	✓	3rd

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

HTTP/3 (QUIC)

HTTP/3 not advertised

REVIEW

HTTP/3 not advertised

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.

Server-Timing Observability

No Server-Timing header found

REVIEW

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.

Page Weight Inventory

Action

50 resources · 4.9 MB · 136 KB savings available

REVIEW

50 resources · 4.9 MB · 136 KB savings available

Page weight 4.9 MB exceeds 1 MB target by 3.9 MB

Got: 4.9 MB Expected: ≤ 1 MB

~136 KB of savings available

28 third-party resources (15% of weight)

5 resources over 200KB

50 resources · 4.9 MiB · 28 third-party 3.9 MiB over 1MB target

Media 46% · 2.3 MiB

Image 36% · 1.8 MiB

JavaScript 15% · 772.7 KiB

Font 1% · 73.7 KiB

CSS 0% · 14.8 KiB

Document 0% · 13.5 KiB

Other 0% · 11.5 KiB

~136.5 KiB of savings available

Remove unused JavaScript: 136.5 KiB

#	Resource	Type	Size	Cache	Unused	3rd party	Issues

50 resources			4.9 MiB

Green Hosting

Action

Whether the site is served from green-energy infrastructure

REVIEW

Green Hosting

No green hosting detected

HTTP Caching

public, max-age=0, must-revalidate

REVIEW

public, max-age=0, must-revalidate

Cache-Control header is set

Got: public, max-age=0, must-revalidate

Last-Modified header present

Cache-Control

public, max-age=0, must-revalidate

Directive	Value	Meaning
public	—	Any cache may store this response
max-age	0	Cache for 0 seconds
must-revalidate	—	Must recheck with server after expiry

A+

Third-Party Impact

15% third-party, 0 ms blocking

PASS

15% third-party, 0 ms blocking

Third-party code accounts for 15% of page weight (768.6 KiB of 4.9 MiB)

Third-party blocking time is low (0 ms)

85%

15%

First-party Third-party

A+

Text Compression

All text resources are compressed

PASS

All text resources are compressed

All text resources are properly compressed.

A+

JS Execution Cost

259ms total JS execution

PASS

259ms total JS execution

https://www.googletagmanager.com/gtag/js?id=G-R22L...: 105ms CPU time

Unattributable: 84ms CPU time

https://vitalitydentistry.com/: 70ms CPU time

Third-party scripts: 105ms (40% of total)

Main Thread Breakdown

Script Evaluation 40% Other 31% Style & Layout 13% Script Parsing & Compilation 9% Rendering 3%

Script	Total	Scripting	Parse/Compile	Party
https://www.googletagmanager.com/gtag/js?id=G-R22LR0L6W2	105ms	85ms	19ms	3rd
Unattributable	84ms	6ms	0ms	1st
https://vitalitydentistry.com/	70ms	2ms	1ms	1st

A+

Font Loading

2 fonts (74 KB)

PASS

2 fonts (74 KB)

2 font(s) use font-display: swap (FOUT risk but functional)

Web fonts

74 KB total

Render-blocking

of 2

Dominant font-display

swap

Most common across fonts

Font loading timeline

Transfer FOIT (block) FOUT (swap)

dm-sans-latin.woff2 woff2 swap

Size 36 KB

Load time 251 ms

Start 513 ms

Risk FOUT — text flashes from fallback to web font

cormorant-garamond-lati... woff2 swap

Size 37 KB

Load time 357 ms

Start 514 ms

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 Caching

All resources properly cached

PASS

All resources properly cached

No caching issues found

All static resources have appropriate caching headers.

A+

Critical Rendering Path

No render-blocking resources

PASS

No render-blocking resources

No render-blocking resources detected

A+

Resource Hints

No optimization needed

PASS

No optimization needed

No resource hint issues

A+

Document Compression

Document response uses brotli

PASS

Document response uses brotli

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+

LCP Image Preload

LCP preload audit not available

PASS

LCP preload audit not available

LCP image preload audit not available for this scan

A+

Main HTML Cache-Control

Main HTML max-age=0 (≤ 5min) is appropriate

PASS

Main HTML max-age=0 (≤ 5min) is appropriate

Got: public, max-age=0, must-revalidate

A+

Server Response Intelligence

2 server-response signal(s) detected

PASS

2 server-response signal(s) detected

`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).

`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.

Asset Compression

No text asset hosts to measure

INFO

No text asset hosts to measure

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 Waterfall

50 requests over 1747ms

INFO

HTML JavaScript CSS Images Fonts XHR/Fetch Other

Third-Party Script Cost

Per-script blocking time, transfer cost, and cache headers

INFO

40% of JavaScript execution is third-party

First-party Third-party 105ms · 196KB · $1/mo

Script	Category	Execution	Transfer	Unused	Monthly Cost	Verdict
Google Tag Manager www.googletagmanager.com	Tag Manager	105ms	196 KB	31%	$1/mo	Optional

Google Tag Manager

Tag Manager

Optional

Execution 105ms

Transfer 196 KB

Unused 31%

Monthly Cost $1/mo

40% 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

How third-party costs are calculated

Real-User Performance (CrUX)

Field metrics from the Chrome User Experience Report

INFO

Chrome User Experience (CrUX)

Real-user metrics from the Chrome UX Report (2026-10-13 — 2026-11-09)

LCP (p75)

922 ms

97% good

INP (p75)

54 ms

98% good

CLS (p75)

0.000

98% good

FCP (p75)

872 ms

TTFB (p75)

368 ms

This origin passes Core Web Vitals assessment

Image Optimization

7 images, 1532 KB total, 1421 KB wasted

INFO

Image Optimization Audit

Total Images

Total Size

1532 KB

Oversized

Wasted

1421 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.