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Performance

· 14 checks — Lighthouse + waterfall + sustainability rolled into one auditable list.
SCORE
67
GRADE
D
FIX
4
REVIEW
3
PASS
5
INFO
2

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

Mobile Desktop
64
Performance Overall performance score (0–100) based on Core Web Vitals and other metrics. 90+ is good.
100
Accessibility Measures how accessible the page is for users with disabilities. Checks color contrast, ARIA labels, and semantic HTML.
92
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.

1.43 s

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

2.98 s

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

268 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.

2.35 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.

4.79 s

Page Load Progression

634 ms
1.3 s
1.9 s
2.5 s
3.2 s
3.8 s
4.4 s
5.1 s
Checks
14
5 PASS 3 REVIEW 4 FIX
F
Page Weight Budget
Action
4.8 MB transferred, 130 requests
FIX
4.8 MB transferred, 130 requests
Critical::
Page weighs 13.9 MB (4.8 MB transferred)
Warning::
JavaScript is 2.8 MB — consider code splitting or lazy loading
Large JavaScript bundles delay interactivity. Split code by route or defer non-critical scripts.
Got: 2.8 MB
Warning::
Images are 1.0 MB — compress or use modern formats
Convert images to WebP/AVIF and resize to display dimensions to reduce transfer size.
Got: 1.0 MB
Info::
CSS is 653 KB — consider purging unused styles
Remove unused CSS rules with tools like PurgeCSS to reduce stylesheet size.
Got: 653 KB
Warning::
130 HTTP requests — consider bundling or reducing
Each request adds latency. Bundle small files, use sprites, or eliminate unnecessary requests.
Info::
Estimated 1.00 g CO2 per page load
4.8 MB / 2.4 MB budget
4.8 MB transferred
130 requests
1.00 g CO2 per page load
JavaScript 2.8 MiB 59%
Images 1.0 MiB 22%
CSS 652.7 KiB 13%
Fonts 191.2 KiB 4%
HTML 29.7 KiB 1%
Other 14.1 KiB 0%
Other 8.1 KiB 0%
Other 7.7 KiB 0%
Other 1008 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

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

Remove unused CSS rules with tools like PurgeCSS to reduce stylesheet size.

Why this matters

CSS bundle is large — purge unused styles (PurgeCSS, Tailwind JIT) to reduce CSS payload.

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
74% third-party, 0 ms blocking
FIX
74% third-party, 0 ms blocking
Warning::
Third-party code accounts for 74% of page weight (3.5 MiB of 4.8 MiB)
Info::
Third-party blocking time is low (0 ms)
26%
74%
First-party Third-party
D
JS Execution Cost
Action
2158ms total JS execution
FIX
2158ms total JS execution
Warning::
https://www.who.int/ScriptResource.axd?d=6DQe8ARl7...: 387ms CPU time
Warning::
https://kendo.cdn.telerik.com/2021.1.119/js/kendo....: 376ms CPU time
Warning::
https://www.who.int/: 338ms CPU time
Warning::
Unattributable: 269ms CPU time
Info::
https://www.who.int/ResourcePackages/WHO/assets/di...: 144ms CPU time
Warning::
Third-party scripts: 1228ms (57% of total)

Main Thread Breakdown

Script Evaluation 44% Other 18% Style & Layout 17% Script Parsing & Compilation 13% Parse HTML & CSS 4%
ScriptTotalScriptingParse/CompileParty
https://www.who.int/ScriptResource.axd?d=6DQe8ARl7A9TiuWej5ttChzH_bH_8oN_s_nT_Gi4bPGf8e5n2fEMKPjzLdvKHVty-4ZMcWf8z4wR7Uoe9uwfRcpGME2zu76GUYKLUjE5oVOWl9suUmdsLOBTG0SyiZPAlK9FJAXJhhse1qDM4EhvGTqNsxl81NUrAtHLeXR4O4h0ZoaW0&t=ffffffff90b6fa90387ms235ms7ms1st
https://kendo.cdn.telerik.com/2021.1.119/js/kendo.all.min.js376ms213ms136ms3rd
https://www.who.int/338ms17ms5ms1st
Unattributable269ms3ms0ms3rd
https://www.who.int/ResourcePackages/WHO/assets/dist/scripts/responsivelylazy.min.js144ms25ms0ms1st
https://www.googletagmanager.com/gtm.js?id=GTM-5QFSQRT99ms86ms13ms3rd
https://static.fundraiseup.com/4557.e38cd0b7a797.4557.js85ms76ms1ms3rd
https://static.fundraiseup.com/checkout-vendors.78ab7844d94042df.js80ms70ms10ms3rd
https://www.googletagmanager.com/gtag/js?id=G-WKG4M0MSB8&cx=c&gtm=4e641179ms66ms13ms3rd
https://cdn.fundraiseup.com/widget/AMEEWKFZ74ms62ms8ms3rd

Showing top 10 of 14 scripts

F
JS Bundles
Action
54 scripts, 2.5 MB unused
FIX
54 scripts, 2.5 MB unused
Warning::
https://kendo.cdn.telerik.com/2021.1.119/js/kendo....: 858 KB unused (79%)
Consider code splitting or tree shaking to reduce unused code.
Warning::
https://kendo.cdn.telerik.com/2021.1.119/js/kendo....: 858 KB unused (79%)
Consider code splitting or tree shaking to reduce unused code.
Warning::
https://static.fundraiseup.com/checkout.098fc4d30f...: 355 KB unused (89%)
Consider code splitting or tree shaking to reduce unused code.
Warning::
https://static.fundraiseup.com/checkout-sentry-ven...: 112 KB unused (100%)
Consider code splitting or tree shaking to reduce unused code.
Warning::
https://static.fundraiseup.com/checkout-vendors.78...: 87 KB unused (83%)
Consider code splitting or tree shaking to reduce unused code.
Info::
Total unused JavaScript: 2.5 MB
2551 KB unused JavaScript

Downloaded but never executed on this page.

ScriptSizeUnusedMinifiedParty
https://kendo.cdn.telerik.com/2021.1.119/js/kendo.all.min.js1088 KB858 KB (79%)✓3rd
https://kendo.cdn.telerik.com/2021.1.119/js/kendo.all.min.js0 KB858 KB (79%)✓3rd
https://static.fundraiseup.com/checkout.098fc4d30f8503a0.js397 KB355 KB (89%)✓3rd
https://static.fundraiseup.com/checkout-sentry-vendor.dda4c7629502a974.js112 KB112 KB (100%)✓3rd
https://static.fundraiseup.com/checkout-vendors.78ab7844d94042df.js105 KB87 KB (83%)✓3rd
https://www.who.int/ScriptResource.axd?d=BipRCKUteAIr0PTUVR7xo6LCrTtac4Cof8FsWeF6Rs8EdDSOktcsIs7LNHQe0q9fjlWLg7K_ACXChvDiB89LssRRoiAaWPfFtKZ5o-YMiaG0eBABoldv--hS66lgbT7E3_ovT6krZJ6OXhPP-uxrsovsKl2AJ6Y1yCcYG8mHshUopGyI0&t=ffffffff90b6fa9094 KB79 KB (89%)✓1st
https://www.googletagmanager.com/gtm.js?id=GTM-5QFSQRT162 KB69 KB (43%)✓3rd
https://www.googletagmanager.com/gtag/js?id=G-WKG4M0MSB8&cx=c&gtm=4e6411156 KB66 KB (42%)✓3rd
https://cdn.fundraiseup.com/widget/AMEEWKFZ70 KB25 KB (37%)✓3rd
https://static.fundraiseup.com/checkout-styles.17c762c93d89a7dd.js22 KB22 KB (100%)✓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

B
Image Optimization
34 images, 0 KB saveable
REVIEW
34 images, 0 KB saveable
Warning::
https://www.who.int/ResourcePackages/WHO/assets/di... is missing width/height — may cause layout shift
Set explicit width and height to prevent CLS.
34 images 1.0 MB
0 oversized -0 KB
4 legacy format
1 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

C
Green Hosting
Action
Whether the site is served from green-energy infrastructure
REVIEW

Green Hosting

No green hosting detected

B
HTTP Caching
public, max-age=0, s-maxage=43200
REVIEW
public, max-age=0, s-maxage=43200
Info::
Cache-Control header is set
Got: public, max-age=0, s-maxage=43200
Info::
CDN TTL: 12 hours (s-maxage=43200)
Info::
Last-Modified header present
Cache-Control

public, max-age=0, s-maxage=43200

DirectiveValueMeaning
public—Any cache may store this response
max-age0Cache for 0 seconds
s-maxage43200CDN caches for 12 hours
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
4 fonts (191 KB)
PASS
4 fonts (191 KB)
Info::
4 font(s) use font-display: swap (FOUT risk but functional)

Web fonts

4

191 KB total

Render-blocking

0

of 4

Dominant font-display

swap

Most common across fonts

Font loading timeline
Transfer FOIT (block) FOUT (swap)
0 ms 1.0 s 2.0 s 3.0 s FCP 1.4 s LCP 3.0 shttps://fonts.gstatic.com/s/notosans/v42/o-0bIpQlx3QUlC5A4PNB6Ryti20_6n1iPHjc5a7du3mhPy0.woff2o-0bIpQlx3QUlC5A4PNB6Ry... https://fonts.gstatic.com/s/notosans/v42/o-0bIpQlx3QUlC5A4PNB6Ryti20_6n1iPHjc5a7du3mhPy0.woff2 — 35.0 KiB — 0 ms — font-display: swaphttps://use.fontawesome.com/releases/v5.15.4/webfonts/fa-solid-900.woff2fa-solid-900.woff2 https://use.fontawesome.com/releases/v5.15.4/webfonts/fa-solid-900.woff2 — 77.0 KiB — 0 ms — font-display: swaphttps://fonts.gstatic.com/s/notosans/v42/o-0bIpQlx3QUlC5A4PNB6Ryti20_6n1iPHjc5ardu3mhPy1Fig.woff2o-0bIpQlx3QUlC5A4PNB6Ry... https://fonts.gstatic.com/s/notosans/v42/o-0bIpQlx3QUlC5A4PNB6Ryti20_6n1iPHjc5ardu3mhPy1Fig.woff2 — 19.6 KiB — 0 ms — font-display: swaphttps://static.fundraiseup.com/common-fonts/ibm-plex-sans/ibmplexsans-v19-600.woff2ibmplexsans-v19-600.woff2 https://static.fundraiseup.com/common-fonts/ibm-plex-sans/ibmplexsans-v19-600.woff2 — 59.6 KiB — 0 ms — font-display: swap
o-0bIpQlx3QUlC5A4PNB6Ry... woff2 swap
Size 35 KB
Load time 0 ms
Start 0 ms
Risk FOUT — text flashes from fallback to web font
fa-solid-900.woff2 woff2 swap
Size 77 KB
Load time 0 ms
Start 0 ms
Risk FOUT — text flashes from fallback to web font
o-0bIpQlx3QUlC5A4PNB6Ry... woff2 swap
Size 20 KB
Load time 0 ms
Start 0 ms
Risk FOUT — text flashes from fallback to web font
ibmplexsans-v19-600.woff2 woff2 swap
Size 60 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
No optimization needed
PASS
No optimization needed
Info::
No resource hint issues
Network Waterfall
130 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
57% of JavaScript execution is third-party
First-party Third-party 1228ms · 952KB · €20/mo
kendo.cdn.telerik.com
Other
Costly
Execution 376ms
Transfer 0 KB
Unused 79%
Monthly Cost €6/mo
Unattributable
Other
Costly
Execution 269ms
Transfer 0 KB
Monthly Cost €4/mo
Google Tag Manager
Tag Manager
Optional
Execution 99ms
Transfer 162 KB
Unused 43%
Monthly Cost €2/mo
static.fundraiseup.com
Other
Optional
Execution 85ms
Transfer 10 KB
Monthly Cost €1/mo
static.fundraiseup.com
Other
Optional
Execution 80ms
Transfer 105 KB
Unused 83%
Monthly Cost €1/mo
Google Tag Manager
Tag Manager
Optional
Execution 79ms
Transfer 156 KB
Unused 42%
Monthly Cost €1/mo
cdn.fundraiseup.com
Other
Optional
Execution 74ms
Transfer 70 KB
Unused 37%
Monthly Cost €1/mo
cdnjs
CDN
Optional
Execution 60ms
Transfer 25 KB
Monthly Cost €1/mo
Microsoft Clarity
Session Replay
Optional
Execution 54ms
Transfer 26 KB
Monthly Cost €1/mo
static.fundraiseup.com
Other
Optional
Execution 50ms
Transfer 397 KB
Unused 89%
Monthly Cost €1/mo

These scripts may cost more than they're worth

  • kendo.cdn.telerik.com adds 376ms and costs ~€6/month
  • Unattributable adds 269ms and costs ~€4/month

57% 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

kendo.cdn.telerik.com takes 376ms 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

79% of kendo.cdn.telerik.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

Unattributable takes 269ms 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

83% of static.fundraiseup.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

89% of static.fundraiseup.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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