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Performance

· 14 checks — Lighthouse + waterfall + sustainability rolled into one auditable list.
SCORE
65
GRADE
D
FIX
4
REVIEW
1
PASS
7
INFO
2

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

Mobile Desktop
34
Performance Overall performance score (0–100) based on Core Web Vitals and other metrics. 90+ is good.
95
Accessibility Measures how accessible the page is for users with disabilities. Checks color contrast, ARIA labels, and semantic HTML.
100
Best Practices Checks for modern web development best practices including HTTPS, no console errors, and secure JavaScript.
92
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.

2.79 s

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

15.72 s

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

9.07 s

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

0.010

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

7.37 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.

30.86 s

Page Load Progression

794 ms
1.6 s
2.4 s
3.2 s
4.0 s
4.8 s
5.6 s
6.4 s
Checks
14
7 PASS 1 REVIEW 4 FIX
F
Page Weight Budget
Action
11.4 MB transferred, 231 requests
FIX
11.4 MB transferred, 231 requests
Critical::
Page weighs 19.5 MB (11.4 MB transferred)
Warning::
JavaScript is 2.7 MB — consider code splitting or lazy loading
Large JavaScript bundles delay interactivity. Split code by route or defer non-critical scripts.
Got: 2.7 MB
Warning::
231 HTTP requests — consider bundling or reducing
Each request adds latency. Bundle small files, use sprites, or eliminate unnecessary requests.
Info::
Estimated 2.4 g CO2 per page load
11.4 MB / 2.4 MB budget
11.4 MB transferred
231 requests
2.4 g CO2 per page load
Other 7.4 MiB 65%
JavaScript 2.7 MiB 24%
Images 692.7 KiB 6%
Other 392.8 KiB 3%
Fonts 166.1 KiB 1%
HTML 77.2 KiB 1%
Other 8.8 KiB 0%
Other 5.5 KiB 0%
Other 0 B 0%
0 2.4 MB 4.9 MB
Over budget

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

Each request adds latency. Bundle small files, use sprites, or eliminate unnecessary requests.

Why this matters

High HTTP request count — bundling, sprite-ing, and HTTP/2 server push can reduce per-request overhead.

Source: web.dev

D
Third-Party Impact
Action
89% third-party, 0 ms blocking
FIX
89% third-party, 0 ms blocking
Warning::
Third-party code accounts for 89% of page weight (10.2 MiB of 11.4 MiB)
Info::
Third-party blocking time is low (0 ms)
89%
First-party Third-party
F
JS Execution Cost
Action
23729ms total JS execution
FIX
23729ms total JS execution
Warning::
https://www.zendesk.com/web-assets/_next/static/ch...: 7070ms CPU time
Warning::
https://www.zendesk.com/: 4998ms CPU time
Warning::
Unattributable: 2679ms CPU time
Warning::
https://fast.wistia.com/assets/external/E-v1.js: 2087ms CPU time
Warning::
https://www.zendesk.com/web-assets/_next/static/ch...: 1361ms CPU time
Info::
Third-party scripts: 8004ms (34% of total)

Main Thread Breakdown

Script Evaluation 57% Other 19% Style & Layout 15% Script Parsing & Compilation 4%
ScriptTotalScriptingParse/CompileParty
https://www.zendesk.com/web-assets/_next/static/chunks/framework-ea624fa794affdb6.js7070ms6511ms13ms1st
https://www.zendesk.com/4998ms71ms4ms1st
Unattributable2679ms509ms0ms3rd
https://fast.wistia.com/assets/external/E-v1.js2087ms1641ms88ms3rd
https://www.zendesk.com/web-assets/_next/static/chunks/pages/_app-0fec37dc12cdc43c.js1361ms434ms29ms1st
https://www.zendesk.com/web-assets/_next/static/chunks/pages/index-b7925a08bc746b7e.js844ms842ms1ms1st
https://www.zendesk.com/web-assets/_next/static/chunks/33208-1b6fe39579ee0eca.js827ms719ms31ms1st
https://static.zdassets.com/web_widget/messenger/latest/web-widget-main-cf0e543.js576ms495ms74ms3rd
https://www.googletagmanager.com/gtm.js?id=GTM-Z4DV521ms445ms70ms3rd
https://www.googletagmanager.com/gtag/destination?id=DC-15086586&cx=c&gtm=4e6411455ms417ms33ms3rd

Showing top 10 of 23 scripts

F
JS Bundles
Action
127 scripts, 999 KB unused
FIX
127 scripts, 999 KB unused
Warning::
https://fast.wistia.com/assets/external/engines/hl...: 122 KB unused (77%)
Consider code splitting or tree shaking to reduce unused code.
Warning::
https://static.zdassets.com/web_widget/messenger/l...: 117 KB unused (49%)
Consider code splitting or tree shaking to reduce unused code.
Warning::
https://www.zendesk.com/web-assets/_next/static/ch...: 80 KB unused (71%)
Consider code splitting or tree shaking to reduce unused code.
Warning::
https://www.zendesk.com/web-assets/_next/static/ch...: 72 KB unused (69%)
Consider code splitting or tree shaking to reduce unused code.
Warning::
https://fast.wistia.com/assets/external/E-v1.js: 70 KB unused (43%)
Consider code splitting or tree shaking to reduce unused code.
Info::
Total unused JavaScript: 999 KB
999 KB unused JavaScript

Downloaded but never executed on this page.

ScriptSizeUnusedMinifiedParty
https://fast.wistia.com/assets/external/engines/hls_video.js@d8ce1c87dcf1b9a4d8e0c7f1f6f913f9fec9e6c5159 KB122 KB (77%)✓3rd
https://static.zdassets.com/web_widget/messenger/latest/web-widget-main-cf0e543.js237 KB117 KB (49%)✓3rd
https://www.zendesk.com/web-assets/_next/static/chunks/fec483df-b3c5d29b019879f5.js114 KB80 KB (71%)✓1st
https://www.zendesk.com/web-assets/_next/static/chunks/42198-eb85e3bc1a71dd92.js105 KB72 KB (69%)✓1st
https://fast.wistia.com/assets/external/E-v1.js162 KB70 KB (43%)✓3rd
https://cdn.cookielaw.org/scripttemplates/202603.1.0/otBannerSdk.js130 KB68 KB (53%)✓3rd
https://www.googletagmanager.com/gtag/destination?id=DC-15086586&cx=c&gtm=4e6411129 KB64 KB (49%)✓3rd
https://www.googletagmanager.com/gtag/js?id=G-FBP7C61M6Z&cx=c&gtm=4e6411163 KB59 KB (36%)✓3rd
https://www.googletagmanager.com/gtag/js?id=AW-972607400&cx=c&gtm=4e6411144 KB59 KB (41%)✓3rd
https://www.googletagmanager.com/gtm.js?id=GTM-Z4DV189 KB55 KB (29%)✓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

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

C
Image Optimization
Action
30 images, 0 KB saveable
REVIEW
30 images, 0 KB saveable
Warning::
https://web-assets.zendesk.com/is/image/zendesk/Ub... is missing width/height — may cause layout shift
Set explicit width and height to prevent CLS.
Warning::
https://web-assets.zendesk.com/is/image/zendesk/Te... is missing width/height — may cause layout shift
Set explicit width and height to prevent CLS.
Warning::
https://web-assets.zendesk.com/is/image/zendesk/Lu... is missing width/height — may cause layout shift
Set explicit width and height to prevent CLS.
Warning::
https://web-assets.zendesk.com/is/image/zendesk/Sq... is missing width/height — may cause layout shift
Set explicit width and height to prevent CLS.
Warning::
https://web-assets.zendesk.com/is/image/zendesk/In... is missing width/height — may cause layout shift
Set explicit width and height to prevent CLS.
Warning::
https://web-assets.zendesk.com/is/image/zendesk/Gr... is missing width/height — may cause layout shift
Set explicit width and height to prevent CLS.
Warning::
https://web-assets.zendesk.com/is/image/zendesk/Te... is missing width/height — may cause layout shift
Set explicit width and height to prevent CLS.
Warning::
https://web-assets.zendesk.com/is/image/zendesk/Sq... is missing width/height — may cause layout shift
Set explicit width and height to prevent CLS.
Warning::
https://web-assets.zendesk.com/is/image/zendesk/Lu... is missing width/height — may cause layout shift
Set explicit width and height to prevent CLS.
Warning::
https://web-assets.zendesk.com/is/image/zendesk/Gr... is missing width/height — may cause layout shift
Set explicit width and height to prevent CLS.
Warning::
https://web-assets.zendesk.com/is/image/zendesk/Li... is missing width/height — may cause layout shift
Set explicit width and height to prevent CLS.
Warning::
https://web-assets.zendesk.com/is/image/zendesk/Ub... is missing width/height — may cause layout shift
Set explicit width and height to prevent CLS.
Warning::
https://web-assets.zendesk.com/is/image/zendesk/St... is missing width/height — may cause layout shift
Set explicit width and height to prevent CLS.
Warning::
https://web-assets.zendesk.com/is/image/zendesk/St... is missing width/height — may cause layout shift
Set explicit width and height to prevent CLS.
Warning::
https://web-assets.zendesk.com/is/image/zendesk/Li... is missing width/height — may cause layout shift
Set explicit width and height to prevent CLS.
Warning::
https://web-assets.zendesk.com/is/image/zendesk/In... is missing width/height — may cause layout shift
Set explicit width and height to prevent CLS.
30 images 693 KB
0 oversized -0 KB
5 legacy format
16 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

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

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
5 fonts (166 KB)
PASS
5 fonts (166 KB)
Info::
5 font(s) use font-display: swap (FOUT risk but functional)

Web fonts

5

166 KB total

Render-blocking

0

of 5

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 14.0 s 16.0 s FCP 2.8 s LCP 15.7 shttps://web-assets.zendesk.com/fonts/VanillaSans/VanillaSans-Medium.woff2VanillaSans-Medium.woff2 https://web-assets.zendesk.com/fonts/VanillaSans/VanillaSans-Medium.woff2 — 33.6 KiB — 0 ms — font-display: swaphttps://web-assets.zendesk.com/fonts/VanillaSans/VanillaSans-Regular.woff2VanillaSans-Regular.woff2 https://web-assets.zendesk.com/fonts/VanillaSans/VanillaSans-Regular.woff2 — 32.6 KiB — 0 ms — font-display: swaphttps://web-assets.zendesk.com/fonts/VanillaSans/VanillaSans-SemiBold.woff2VanillaSans-SemiBold.woff2 https://web-assets.zendesk.com/fonts/VanillaSans/VanillaSans-SemiBold.woff2 — 33.4 KiB — 0 ms — font-display: swaphttps://web-assets.zendesk.com/fonts/VanillaSans/VanillaSans-Bold.woff2VanillaSans-Bold.woff2 https://web-assets.zendesk.com/fonts/VanillaSans/VanillaSans-Bold.woff2 — 33.5 KiB — 0 ms — font-display: swaphttps://web-assets.zendesk.com/fonts/VanillaSans/VanillaSans-Light.woff2VanillaSans-Light.woff2 https://web-assets.zendesk.com/fonts/VanillaSans/VanillaSans-Light.woff2 — 33.1 KiB — 0 ms — font-display: swap
VanillaSans-Medium.woff2 woff2 swap
Size 34 KB
Load time 0 ms
Start 0 ms
Risk FOUT — text flashes from fallback to web font
VanillaSans-Regular.woff2 woff2 swap
Size 33 KB
Load time 0 ms
Start 0 ms
Risk FOUT — text flashes from fallback to web font
VanillaSans-SemiBold.woff2 woff2 swap
Size 33 KB
Load time 0 ms
Start 0 ms
Risk FOUT — text flashes from fallback to web font
VanillaSans-Bold.woff2 woff2 swap
Size 34 KB
Load time 0 ms
Start 0 ms
Risk FOUT — text flashes from fallback to web font
VanillaSans-Light.woff2 woff2 swap
Size 33 KB
Load time 0 ms
Start 0 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
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
2
preload
1
dns-prefetch
3
prefetch
—

6 resource hints configured

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

A+
HTTP Caching
max-age=3600 (1 hour)
PASS
max-age=3600 (1 hour)
Info::
Cache-Control header is set
Got: public, max-age=3600
Info::
Effective TTL: 1 hour (max-age=3600)
Info::
Last-Modified header present
Cache-Control

public, max-age=3600

DirectiveValueMeaning
public—Any cache may store this response
max-age3600Cache for 1 hour
Effective TTL: 3600 seconds
Network Waterfall
231 requests over 0ms
INFO

Performance analysis not available for this result.

Third-Party Script Cost
Per-script blocking time, transfer cost, and cache headers
INFO
34% of JavaScript execution is third-party
First-party Third-party 8004ms · 1271KB · $150/mo
Unattributable
Other
Costly
Execution 2679ms
Transfer 0 KB
Monthly Cost $50/mo
fast.wistia.com
Other
Costly
Execution 2087ms
Transfer 162 KB
Unused 43%
Monthly Cost $39/mo
Zendesk Widget
Customer Support
Costly
Execution 576ms
Transfer 237 KB
Unused 49%
Monthly Cost $11/mo
Google Tag Manager
Tag Manager
Costly
Execution 521ms
Transfer 189 KB
Unused 29%
Monthly Cost $10/mo
Google Tag Manager
Tag Manager
Costly
Execution 455ms
Transfer 129 KB
Unused 49%
Monthly Cost $9/mo
OneTrust
Consent
Essential
Execution 350ms
Transfer 130 KB
Unused 53%
Monthly Cost $7/mo
Google Tag Manager
Tag Manager
Costly
Execution 302ms
Transfer 163 KB
Unused 36%
Monthly Cost $6/mo
Zendesk Widget
Customer Support
Costly
Execution 251ms
Transfer 22 KB
Monthly Cost $5/mo
Zendesk Widget
Customer Support
Costly
Execution 229ms
Transfer 5 KB
Monthly Cost $4/mo
Google Tag Manager
Tag Manager
Costly
Execution 228ms
Transfer 144 KB
Unused 41%
Monthly Cost $4/mo
fast.wistia.com
Other
Optional
Execution 152ms
Transfer 42 KB
Unused 69%
Monthly Cost $3/mo
fast.wistia.com
Other
Optional
Execution 110ms
Transfer 43 KB
Unused 65%
Monthly Cost $2/mo
Zendesk Widget
Customer Support
Optional
Execution 65ms
Transfer 4 KB
Monthly Cost $1/mo

These scripts may cost more than they're worth

  • Unattributable adds 2679ms and costs ~$50/month
  • fast.wistia.com adds 2087ms and costs ~$39/month
  • Zendesk Widget adds 576ms and costs ~$11/month
  • Google Tag Manager adds 521ms and costs ~$10/month
  • Google Tag Manager adds 455ms and costs ~$9/month
  • Google Tag Manager adds 302ms and costs ~$6/month
  • Zendesk Widget adds 251ms and costs ~$5/month
  • Zendesk Widget adds 229ms and costs ~$4/month
  • Google Tag Manager adds 228ms and costs ~$4/month

Unattributable takes 2679ms 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

fast.wistia.com takes 2087ms 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

Zendesk Widget takes 576ms 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

Google Tag Manager takes 521ms 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

Google Tag Manager takes 455ms 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

53% of OneTrust'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

Google Tag Manager takes 302ms 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

Zendesk Widget takes 251ms 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

Zendesk Widget takes 229ms 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

Google Tag Manager takes 228ms 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

69% of fast.wistia.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

65% of fast.wistia.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

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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