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
29 images, 0 KB saveable
REVIEW
29 images, 0 KB saveable
Warning::
!
https://www.weforum.org/a-weekly-logo.svg is missing width/height — may cause layout shift
Set explicit width and height to prevent CLS.
29images3.0 MB
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
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
3 fonts (378 KB)
PASS
3 fonts (378 KB)
Info::
i
3 font(s) use font-display: swap (FOUT risk but functional)
Web fonts
3
378 KB total
Render-blocking
0
of 3
Dominant font-display
swap
Most common across fonts
Font loading timeline
TransferFOIT (block)FOUT (swap)
AkkuratLLWeb-Regular.woff2woff2swap
Size108 KB
Load time49 ms
Start724 ms
RiskFOUT — 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
AkkuratLLWeb-Black.woff2woff2swap
Size112 KB
Load time48 ms
Start897 ms
RiskFOUT — 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
AkkuratLLWeb-Bold.woffwoffswap
Size158 KB
Load time90 ms
Start897 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 ~236 KB and ~472 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
102 requests over 6198ms
INFO
HTML JavaScript CSS Images Fonts XHR/Fetch Other
Third-Party Script Cost
Per-script blocking time, transfer cost, and cache headers
INFO
100%of JavaScript execution is third-party
First-party Third-party3689ms · 2334KB · €40/mo
Script
Category
Execution
Transfer
Unused
Monthly Cost
Verdict
www.weforum.org
www.weforum.org
Other
736ms
55 KB
—
€8/mo
Costly
www.weforum.org
www.weforum.org
Other
575ms
108 KB
—
€6/mo
Costly
mfe.weforum.org
mfe.weforum.org
Other
313ms
384 KB
30%
€3/mo
Costly
consent.cookiebot.com
consent.cookiebot.com
Other
277ms
121 KB
21%
€3/mo
Costly
Unattributable
Unattributable
Other
263ms
0 KB
—
€3/mo
Costly
Google Tag Manager
www.googletagmanager.com
Tag Manager
242ms
175 KB
36%
€3/mo
Costly
Google Tag Manager
www.googletagmanager.com
Tag Manager
228ms
172 KB
40%
€2/mo
Costly
www.weforum.org
www.weforum.org
Other
208ms
438 KB
46%
€2/mo
Costly
mfe.weforum.org
mfe.weforum.org
Other
202ms
1 KB
—
€2/mo
Costly
dev.visualwebsiteoptimizer.com
dev.visualwebsiteoptimizer.com
Other
182ms
97 KB
63%
€2/mo
Optional
www.weforum.org
www.weforum.org
Other
135ms
225 KB
57%
€1/mo
Optional
Google Tag Manager
www.googletagmanager.com
Tag Manager
77ms
176 KB
36%
€1/mo
Optional
www.weforum.org
www.weforum.org
Other
75ms
28 KB
91%
€1/mo
Optional
Google Tag Manager
www.googletagmanager.com
Tag Manager
66ms
173 KB
42%
€1/mo
Optional
Google Tag Manager
www.googletagmanager.com
Tag Manager
59ms
146 KB
44%
€1/mo
Optional
consent.cookiebot.com
consent.cookiebot.com
Other
51ms
36 KB
—
€1/mo
Optional
www.weforum.org
Other
Costly
Execution736ms
Transfer55 KB
Monthly Cost€8/mo
www.weforum.org
Other
Costly
Execution575ms
Transfer108 KB
Monthly Cost€6/mo
mfe.weforum.org
Other
Costly
Execution313ms
Transfer384 KB
Unused30%
Monthly Cost€3/mo
consent.cookiebot.com
Other
Costly
Execution277ms
Transfer121 KB
Unused21%
Monthly Cost€3/mo
Unattributable
Other
Costly
Execution263ms
Transfer0 KB
Monthly Cost€3/mo
Google Tag Manager
Tag Manager
Costly
Execution242ms
Transfer175 KB
Unused36%
Monthly Cost€3/mo
Google Tag Manager
Tag Manager
Costly
Execution228ms
Transfer172 KB
Unused40%
Monthly Cost€2/mo
www.weforum.org
Other
Costly
Execution208ms
Transfer438 KB
Unused46%
Monthly Cost€2/mo
mfe.weforum.org
Other
Costly
Execution202ms
Transfer1 KB
Monthly Cost€2/mo
dev.visualwebsiteoptimizer.com
Other
Optional
Execution182ms
Transfer97 KB
Unused63%
Monthly Cost€2/mo
www.weforum.org
Other
Optional
Execution135ms
Transfer225 KB
Unused57%
Monthly Cost€1/mo
Google Tag Manager
Tag Manager
Optional
Execution77ms
Transfer176 KB
Unused36%
Monthly Cost€1/mo
www.weforum.org
Other
Optional
Execution75ms
Transfer28 KB
Unused91%
Monthly Cost€1/mo
Google Tag Manager
Tag Manager
Optional
Execution66ms
Transfer173 KB
Unused42%
Monthly Cost€1/mo
Google Tag Manager
Tag Manager
Optional
Execution59ms
Transfer146 KB
Unused44%
Monthly Cost€1/mo
consent.cookiebot.com
Other
Optional
Execution51ms
Transfer36 KB
Monthly Cost€1/mo
These scripts may cost more than they're worth
www.weforum.org adds 736ms and costs ~€8/month
www.weforum.org adds 575ms and costs ~€6/month
mfe.weforum.org adds 313ms and costs ~€3/month
consent.cookiebot.com adds 277ms and costs ~€3/month
Unattributable adds 263ms and costs ~€3/month
Google Tag Manager adds 242ms and costs ~€3/month
Google Tag Manager adds 228ms and costs ~€2/month
www.weforum.org adds 208ms and costs ~€2/month
mfe.weforum.org adds 202ms and costs ~€2/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
www.weforum.org takes 736ms 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
www.weforum.org takes 575ms 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
mfe.weforum.org takes 313ms 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
consent.cookiebot.com takes 277ms 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 263ms 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 242ms 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
www.weforum.org takes 208ms 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
mfe.weforum.org takes 202ms 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
63% of dev.visualwebsiteoptimizer.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
57% of www.weforum.org'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
91% of www.weforum.org'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.