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Performance

· 14 checks — Lighthouse + waterfall + sustainability rolled into one auditable list.
SCORE
74
GRADE
C
FIX
5
REVIEW
2
PASS
5
INFO
2

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

Mobile Desktop
80
Performance Overall performance score (0–100) based on Core Web Vitals and other metrics. 90+ is good.
97
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.
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.

1.66 s

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

2.16 s

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

24 ms

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

0.002

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

1.93 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.

3.07 s

Page Load Progression

1.9 s
3.8 s
5.6 s
7.5 s
9.4 s
11.3 s
13.1 s
15.0 s
Checks
14
5 PASS 2 REVIEW 5 FIX
F
Page Weight Budget
Action
24.8 MB transferred, 99 requests
FIX
24.8 MB transferred, 99 requests
Critical::
Page weighs 28.6 MB (24.8 MB transferred)
Info::
Fonts are 1.1 MB — consider subsetting or using system fonts
Subset fonts to include only used characters, or switch to system font stacks.
Got: 1.1 MB
Warning::
JavaScript is 851 KB — consider code splitting or lazy loading
Large JavaScript bundles delay interactivity. Split code by route or defer non-critical scripts.
Got: 851 KB
Info::
99 HTTP requests
Info::
Estimated 5.2 g CO2 per page load
24.8 MB / 2.4 MB budget
24.8 MB transferred
99 requests
5.2 g CO2 per page load
Other 22.0 MiB 89%
Fonts 1.1 MiB 5%
JavaScript 851.4 KiB 3%
Images 665.4 KiB 3%
CSS 89.4 KiB 0%
Other 51.0 KiB 0%
HTML 33.4 KiB 0%
Other 15.2 KiB 0%
Other 5.0 KiB 0%
Other 0 B 0%
0 2.4 MB 4.9 MB
Over budget

Subset fonts to include only used characters, or switch to system font stacks.

Why this matters

Font payload is large — subset to used glyphs only, or fall back to system fonts (zero load time).

Source: web.dev font loading

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

D
Third-Party Impact
Action
100% third-party, 0 ms blocking
FIX
100% third-party, 0 ms blocking
Warning::
Third-party code accounts for 100% of page weight (24.8 MiB of 24.8 MiB)
Info::
Third-party blocking time is low (0 ms)
100%
First-party Third-party
D
JS Execution Cost
Action
2662ms total JS execution
FIX
2662ms total JS execution
Warning::
https://assets.prezicdn.net/assets-versioned/stati...: 1171ms CPU time
Warning::
https://prezi.com/: 628ms CPU time
Warning::
Unattributable: 417ms CPU time
Info::
https://assets.prezicdn.net/assets-versioned/stati...: 186ms CPU time
Info::
https://www.googletagmanager.com/gtm.js?id=GTM-MQ6...: 100ms CPU time
Warning::
Third-party scripts: 2662ms (100% of total)

Main Thread Breakdown

Script Evaluation 35% Other 35% Style & Layout 13% Rendering 13%
ScriptTotalScriptingParse/CompileParty
https://assets.prezicdn.net/assets-versioned/staticpages-versioned/v1.0-458-gf616c699ae-r24091638522a1/lib/sentry/sentry-errors-only.min.js1171ms448ms1ms3rd
https://prezi.com/628ms23ms2ms3rd
Unattributable417ms37ms0ms3rd
https://assets.prezicdn.net/assets-versioned/staticpages-versioned/v1.0-458-gf616c699ae-r24091638522a1/staticpages/webflow/js/webflow.abd70382.d731504945e41d8c.js186ms171ms0ms3rd
https://www.googletagmanager.com/gtm.js?id=GTM-MQ6FG2100ms81ms17ms3rd
https://www.googletagmanager.com/gtag/js?id=AW-1001687149&cx=c&gtm=4e646092ms83ms8ms3rd
https://cdn.cookielaw.org/scripttemplates/202601.1.0/otBannerSdk.js67ms46ms10ms3rd
D
JS Bundles
Action
24 scripts, 308 KB unused
FIX
24 scripts, 308 KB unused
Warning::
https://www.googletagmanager.com/gtm.js?id=GTM-MQ6...: 76 KB unused (42%)
Consider code splitting or tree shaking to reduce unused code.
Warning::
https://cdn.cookielaw.org/scripttemplates/202601.1...: 66 KB unused (52%)
Consider code splitting or tree shaking to reduce unused code.
Warning::
https://accounts.google.com/gsi/client?hl=en: 66 KB unused (71%)
Consider code splitting or tree shaking to reduce unused code.
Warning::
https://www.googletagmanager.com/gtag/js?id=AW-100...: 65 KB unused (44%)
Consider code splitting or tree shaking to reduce unused code.
Warning::
https://script.hotjar.com/modules.6a0f3932cb1341a3...: 36 KB unused (63%)
Consider code splitting or tree shaking to reduce unused code.
Info::
Total unused JavaScript: 308 KB
308 KB unused JavaScript

Downloaded but never executed on this page.

ScriptSizeUnusedMinifiedParty
https://www.googletagmanager.com/gtm.js?id=GTM-MQ6FG2183 KB76 KB (42%)✓3rd
https://cdn.cookielaw.org/scripttemplates/202601.1.0/otBannerSdk.js127 KB66 KB (52%)✓3rd
https://accounts.google.com/gsi/client?hl=en93 KB66 KB (71%)✓3rd
https://www.googletagmanager.com/gtag/js?id=AW-1001687149&cx=c&gtm=4e6460146 KB65 KB (44%)✓3rd
https://script.hotjar.com/modules.6a0f3932cb1341a35c18.js57 KB36 KB (63%)✓3rd
https://assets.prezicdn.net/assets-versioned/staticpages-versioned/v1.0-458-gf616c699ae-r24091638522a1/staticpages/webflow/js/webflow.schunk.ae9b3d056ada97a5.js68 KB—✓3rd
https://d3e54v103j8qbb.cloudfront.net/js/jquery-3.5.1.min.dc5e7f18c8.js?site=64be3ac6d7e811ba37809e1c30 KB—✓3rd
https://assets.prezicdn.net/assets-versioned/staticpages-versioned/v1.0-458-gf616c699ae-r24091638522a1/staticpages/webflow/js/webflow.abd70382.d731504945e41d8c.js2 KB—✓3rd
https://cdn.jsdelivr.net/npm/gsap@3.13.0/dist/gsap.min.js29 KB—✓3rd
https://cdn.jsdelivr.net/npm/gsap@3.13.0/dist/TextPlugin.min.js4 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

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

F
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.

No Cache-Control header

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

C
Image Optimization
Action
34 images, 0 KB saveable
REVIEW
34 images, 0 KB saveable
Warning::
https://assets.prezicdn.net/assets-versioned/stati... is missing width/height — may cause layout shift
Set explicit width and height to prevent CLS.
Warning::
https://assets.prezicdn.net/assets-versioned/stati... is missing width/height — may cause layout shift
Set explicit width and height to prevent CLS.
Warning::
https://assets.prezicdn.net/assets-versioned/stati... is missing width/height — may cause layout shift
Set explicit width and height to prevent CLS.
Warning::
https://assets.prezicdn.net/assets-versioned/stati... is missing width/height — may cause layout shift
Set explicit width and height to prevent CLS.
Warning::
https://assets.prezicdn.net/assets-versioned/stati... is missing width/height — may cause layout shift
Set explicit width and height to prevent CLS.
Warning::
https://assets.prezicdn.net/assets-versioned/stati... is missing width/height — may cause layout shift
Set explicit width and height to prevent CLS.
Warning::
https://assets.prezicdn.net/assets-versioned/stati... is missing width/height — may cause layout shift
Set explicit width and height to prevent CLS.
Warning::
https://cdn.prod.website-files.com/6022af993a6b219... is missing width/height — may cause layout shift
Set explicit width and height to prevent CLS.
Warning::
https://assets.prezicdn.net/assets-versioned/stati... is missing width/height — may cause layout shift
Set explicit width and height to prevent CLS.
Warning::
https://assets.prezicdn.net/assets-versioned/stati... is missing width/height — may cause layout shift
Set explicit width and height to prevent CLS.
Warning::
is missing width/height — may cause layout shift
Set explicit width and height to prevent CLS.
Warning::
https://assets.prezicdn.net/assets-versioned/stati... is missing width/height — may cause layout shift
Set explicit width and height to prevent CLS.
Warning::
https://assets.prezicdn.net/assets-versioned/stati... is missing width/height — may cause layout shift
Set explicit width and height to prevent CLS.
34 images 665 KB
0 oversized -0 KB
29 legacy format
13 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

Performance issues directly impact user engagement and conversion rates.

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

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
10 fonts (1177 KB)
PASS
10 fonts (1177 KB)
Info::
10 font(s) use font-display: swap (FOUT risk but functional)

Web fonts

10

1177 KB total

Render-blocking

0

of 10

Dominant font-display

swap

Most common across fonts

Font loading timeline
Transfer FOIT (block) FOUT (swap)
0 ms 500 ms 1.0 s 1.5 s 2.0 s FCP 1.7 s LCP 2.2 shttps://cdn.prod.website-files.com/64be3ac6d7e811ba37809e1c/67bcd424adeccc775fb15ff5_Inter.var.woff267bcd424adeccc775fb15ff... https://cdn.prod.website-files.com/64be3ac6d7e811ba37809e1c/67bcd424adeccc775fb15ff5_Inter.var.woff2 — 318.0 KiB — 0 ms — font-display: swaphttps://use.typekit.net/af/d507b5/0000000000000000775ac6b4/31/l?primer=f592e0a4b9356877842506ce344308576437e4f677d7c9b78ca2162e6cad991a&fvd=n7&v=3l https://use.typekit.net/af/d507b5/0000000000000000775ac6b4/31/l?primer=f592e0a4b9356877842506ce344308576437e4f677d7c9b78ca2162e6cad991a&fvd=n7&v=3 — 94.0 KiB — 0 ms — font-display: swaphttps://use.typekit.net/af/58a628/0000000000000000775ac6ba/31/l?primer=f592e0a4b9356877842506ce344308576437e4f677d7c9b78ca2162e6cad991a&fvd=n8&v=3l https://use.typekit.net/af/58a628/0000000000000000775ac6ba/31/l?primer=f592e0a4b9356877842506ce344308576437e4f677d7c9b78ca2162e6cad991a&fvd=n8&v=3 — 95.4 KiB — 0 ms — font-display: swaphttps://use.typekit.net/af/29d8c9/0000000000000000775ac6af/31/l?primer=f592e0a4b9356877842506ce344308576437e4f677d7c9b78ca2162e6cad991a&fvd=n4&v=3l https://use.typekit.net/af/29d8c9/0000000000000000775ac6af/31/l?primer=f592e0a4b9356877842506ce344308576437e4f677d7c9b78ca2162e6cad991a&fvd=n4&v=3 — 93.7 KiB — 0 ms — font-display: swaphttps://use.typekit.net/af/f855f7/0000000000000000775ac6b8/31/l?primer=f592e0a4b9356877842506ce344308576437e4f677d7c9b78ca2162e6cad991a&fvd=i4&v=3l https://use.typekit.net/af/f855f7/0000000000000000775ac6b8/31/l?primer=f592e0a4b9356877842506ce344308576437e4f677d7c9b78ca2162e6cad991a&fvd=i4&v=3 — 96.1 KiB — 0 ms — font-display: swaphttps://use.typekit.net/af/7e874d/0000000000000000775ac6b9/31/l?primer=f592e0a4b9356877842506ce344308576437e4f677d7c9b78ca2162e6cad991a&fvd=i7&v=3l https://use.typekit.net/af/7e874d/0000000000000000775ac6b9/31/l?primer=f592e0a4b9356877842506ce344308576437e4f677d7c9b78ca2162e6cad991a&fvd=i7&v=3 — 97.2 KiB — 0 ms — font-display: swaphttps://use.typekit.net/af/85479d/0000000000000000775ac6be/31/l?primer=f592e0a4b9356877842506ce344308576437e4f677d7c9b78ca2162e6cad991a&fvd=n6&v=3l https://use.typekit.net/af/85479d/0000000000000000775ac6be/31/l?primer=f592e0a4b9356877842506ce344308576437e4f677d7c9b78ca2162e6cad991a&fvd=n6&v=3 — 94.9 KiB — 0 ms — font-display: swaphttps://use.typekit.net/af/afac1d/0000000000000000775ac6b5/31/l?primer=f592e0a4b9356877842506ce344308576437e4f677d7c9b78ca2162e6cad991a&fvd=i6&v=3l https://use.typekit.net/af/afac1d/0000000000000000775ac6b5/31/l?primer=f592e0a4b9356877842506ce344308576437e4f677d7c9b78ca2162e6cad991a&fvd=i6&v=3 — 97.3 KiB — 0 ms — font-display: swaphttps://use.typekit.net/af/12e45a/0000000000000000775ac6bd/31/l?primer=f592e0a4b9356877842506ce344308576437e4f677d7c9b78ca2162e6cad991a&fvd=n5&v=3l https://use.typekit.net/af/12e45a/0000000000000000775ac6bd/31/l?primer=f592e0a4b9356877842506ce344308576437e4f677d7c9b78ca2162e6cad991a&fvd=n5&v=3 — 93.4 KiB — 0 ms — font-display: swaphttps://use.typekit.net/af/a28944/0000000000000000775ac6bf/31/l?primer=f592e0a4b9356877842506ce344308576437e4f677d7c9b78ca2162e6cad991a&fvd=i5&v=3l https://use.typekit.net/af/a28944/0000000000000000775ac6bf/31/l?primer=f592e0a4b9356877842506ce344308576437e4f677d7c9b78ca2162e6cad991a&fvd=i5&v=3 — 97.1 KiB — 0 ms — font-display: swap
67bcd424adeccc775fb15ff... woff2 swap
Size 318 KB
Load time 0 ms
Start 0 ms
Risk FOUT — text flashes from fallback to web font
  • Subset this font — over 100 KB suggests Latin Extended or full glyph coverage that most pages don't need
l woff2 swap
Size 94 KB
Load time 0 ms
Start 0 ms
Risk FOUT — text flashes from fallback to web font
l woff2 swap
Size 95 KB
Load time 0 ms
Start 0 ms
Risk FOUT — text flashes from fallback to web font
l woff2 swap
Size 94 KB
Load time 0 ms
Start 0 ms
Risk FOUT — text flashes from fallback to web font
l woff2 swap
Size 96 KB
Load time 0 ms
Start 0 ms
Risk FOUT — text flashes from fallback to web font
l woff2 swap
Size 97 KB
Load time 0 ms
Start 0 ms
Risk FOUT — text flashes from fallback to web font
l woff2 swap
Size 95 KB
Load time 0 ms
Start 0 ms
Risk FOUT — text flashes from fallback to web font
l woff2 swap
Size 97 KB
Load time 0 ms
Start 0 ms
Risk FOUT — text flashes from fallback to web font
l woff2 swap
Size 93 KB
Load time 0 ms
Start 0 ms
Risk FOUT — text flashes from fallback to web font
l woff2 swap
Size 97 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)

Fixing the unchecked items could save ~159 KB and ~318 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
No optimization needed
PASS
No optimization needed
Info::
No resource hint issues
Network Waterfall
99 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
100% of JavaScript execution is third-party
First-party Third-party 2662ms · 516KB · €46/mo
assets.prezicdn.net
Other
Costly
Execution 1171ms
Transfer 25 KB
Monthly Cost €20/mo
prezi.com
Other
Costly
Execution 628ms
Transfer 33 KB
Monthly Cost €11/mo
Unattributable
Other
Costly
Execution 417ms
Transfer 0 KB
Monthly Cost €7/mo
assets.prezicdn.net
Other
Optional
Execution 186ms
Transfer 2 KB
Monthly Cost €3/mo
Google Tag Manager
Tag Manager
Optional
Execution 100ms
Transfer 183 KB
Unused 42%
Monthly Cost €2/mo
Google Tag Manager
Tag Manager
Optional
Execution 92ms
Transfer 146 KB
Unused 44%
Monthly Cost €2/mo
OneTrust
Consent
Essential
Execution 67ms
Transfer 127 KB
Unused 52%
Monthly Cost €1/mo

These scripts may cost more than they're worth

  • assets.prezicdn.net adds 1171ms and costs ~€20/month
  • prezi.com adds 628ms and costs ~€11/month
  • Unattributable adds 417ms and costs ~€7/month

100% 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

assets.prezicdn.net takes 1171ms 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

prezi.com takes 628ms 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

Unattributable takes 417ms 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 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

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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