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
27 images, 0 KB saveable
REVIEW
27 images, 0 KB saveable
Warning::
!
https://www.iberia.com/wcs/imagenes/ofertas/home/h... is missing width/height — may cause layout shift
Set explicit width and height to prevent CLS.
Warning::
!
https://www.iberia.com/wcs/imagenes/ofertas/bah/he... is missing width/height — may cause layout shift
Set explicit width and height to prevent CLS.
Warning::
!
https://www.iberia.com/wcs/imagenes/home/herobanne... is missing width/height — may cause layout shift
Set explicit width and height to prevent CLS.
Warning::
!
https://www.iberia.com/wcs/imagenes/home/pod/pod_v... is missing width/height — may cause layout shift
Set explicit width and height to prevent CLS.
Warning::
!
https://www.iberia.com/wcs/imagenes/ofertas/bah/po... is missing width/height — may cause layout shift
Set explicit width and height to prevent CLS.
Warning::
!
https://www.iberia.com/wcs/imagenes/ofertas/bah/po... is missing width/height — may cause layout shift
Set explicit width and height to prevent CLS.
Warning::
!
data:image/gif;base64,R0lGODlhAQABAAAAACH5BAEKAAEA... is missing width/height — may cause layout shift
Set explicit width and height to prevent CLS.
Warning::
!
https://www.iberia.com/wcs/imagenes/ofertas/rutas_... is missing width/height — may cause layout shift
Set explicit width and height to prevent CLS.
Warning::
!
https://www.iberia.com/wcs/imagenes/home/promo/her... is missing width/height — may cause layout shift
Set explicit width and height to prevent CLS.
Warning::
!
https://www.iberia.com/wcs/imagenes/ofertas/croaci... is missing width/height — may cause layout shift
Set explicit width and height to prevent CLS.
27images645 KB
0oversized-0 KB
15legacy format
10missing 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
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
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 (138 KB)
PASS
3 fonts (138 KB)
Info::
i
3 font(s) use font-display: swap (FOUT risk but functional)
Web fonts
3
138 KB total
Render-blocking
0
of 3
Dominant font-display
swap
Most common across fonts
Font loading timeline
TransferFOIT (block)FOUT (swap)
iberia.woff2woff2swap
Size73 KB
Load time59 ms
Start273 ms
RiskFOUT — text flashes from fallback to web font
iberiaheadline.woff2woff2swap
Size28 KB
Load time54 ms
Start274 ms
RiskFOUT — text flashes from fallback to web font
iberiatext.woff2woff2swap
Size38 KB
Load time55 ms
Start274 ms
RiskFOUT — 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
8 hints, 0 missing preconnects
PASS
8 hints, 0 missing preconnects
Info::
✓
Page uses 8 resource hint(s)
Current Resource Hints
preconnect—
preload
3
dns-prefetch
5
prefetch—
8 resource hints configured
A+
Render-Blocking Resources
No render-blocking resources detected
PASS
No render-blocking resources detected
Info::
✓
No render-blocking resources detected in <head>
A+
Third-Party Resources
No third-party resources detected
PASS
No third-party resources detected
Network Waterfall
146 requests over 10680ms
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-party19103ms · 2507KB · €207/mo
Script
Category
Execution
Transfer
Unused
Monthly Cost
Verdict
www.iberia.com
www.iberia.com
Other
2494ms
263 KB
78%
€27/mo
Costly
www.iberia.com
www.iberia.com
Other
1940ms
64 KB
—
€21/mo
Costly
www.iberia.com
www.iberia.com
Other
1469ms
129 KB
40%
€16/mo
Costly
www.iberia.com
www.iberia.com
Other
1287ms
70 KB
80%
€14/mo
Costly
www.iberia.com
www.iberia.com
Other
1268ms
153 KB
18%
€14/mo
Costly
Unattributable
Unattributable
Other
1258ms
0 KB
—
€14/mo
Costly
cdn.quantummetric.com
cdn.quantummetric.com
Other
1146ms
144 KB
38%
€12/mo
Costly
sb.monetate.net
sb.monetate.net
Other
976ms
14 KB
—
€11/mo
Costly
www.iberia.com
www.iberia.com
Other
955ms
71 KB
54%
€10/mo
Costly
www.iberia.com
www.iberia.com
Other
758ms
1 KB
21%
€8/mo
Costly
www.iberia.com
www.iberia.com
Other
749ms
91 KB
63%
€8/mo
Costly
Google Tag Manager
www.googletagmanager.com
Tag Manager
632ms
170 KB
29%
€7/mo
Costly
euob.forroundprince.com
euob.forroundprince.com
Other
557ms
45 KB
—
€6/mo
Costly
sb.monetate.net
sb.monetate.net
Other
480ms
2 KB
—
€5/mo
Costly
Google Tag Manager
www.googletagmanager.com
Tag Manager
387ms
164 KB
39%
€4/mo
Costly
Google Tag Manager
www.googletagmanager.com
Tag Manager
306ms
193 KB
31%
€3/mo
Costly
sb.monetate.net
sb.monetate.net
Other
289ms
2 KB
—
€3/mo
Costly
www.iberia.com
www.iberia.com
Other
244ms
213 KB
61%
€3/mo
Costly
Google Tag Manager
www.googletagmanager.com
Tag Manager
209ms
144 KB
49%
€2/mo
Costly
obseu.forroundprince.com
obseu.forroundprince.com
Other
179ms
2 KB
—
€2/mo
Optional
Google Tag Manager
www.googletagmanager.com
Tag Manager
168ms
130 KB
50%
€2/mo
Optional
se.monetate.net
se.monetate.net
Other
166ms
65 KB
68%
€2/mo
Optional
sb.monetate.net
sb.monetate.net
Other
154ms
7 KB
—
€2/mo
Optional
sb.monetate.net
sb.monetate.net
Other
150ms
4 KB
—
€2/mo
Optional
www.iberia.com
www.iberia.com
Other
137ms
9 KB
—
€1/mo
Optional
sdk.inbenta.io
sdk.inbenta.io
Other
136ms
150 KB
70%
€1/mo
Optional
cdn-ukwest.onetrust.com
cdn-ukwest.onetrust.com
Other
129ms
9 KB
—
€1/mo
Optional
www.iberia.com
www.iberia.com
Other
92ms
40 KB
—
€1/mo
Optional
www.iberia.com
www.iberia.com
Other
82ms
42 KB
—
€1/mo
Optional
af.monetate.net
af.monetate.net
Other
82ms
3 KB
—
€1/mo
Optional
cdn-ukwest.onetrust.com
cdn-ukwest.onetrust.com
Other
64ms
94 KB
53%
€1/mo
Optional
Bing UET
bat.bing.com
Advertising
57ms
16 KB
—
€1/mo
Optional
sb.monetate.net
sb.monetate.net
Other
55ms
5 KB
—
€1/mo
Optional
www.iberia.com
www.iberia.com
Other
51ms
0 KB
—
€1/mo
Optional
www.iberia.com
Other
Costly
Execution2494ms
Transfer263 KB
Unused78%
Monthly Cost€27/mo
www.iberia.com
Other
Costly
Execution1940ms
Transfer64 KB
Monthly Cost€21/mo
www.iberia.com
Other
Costly
Execution1469ms
Transfer129 KB
Unused40%
Monthly Cost€16/mo
www.iberia.com
Other
Costly
Execution1287ms
Transfer70 KB
Unused80%
Monthly Cost€14/mo
www.iberia.com
Other
Costly
Execution1268ms
Transfer153 KB
Unused18%
Monthly Cost€14/mo
Unattributable
Other
Costly
Execution1258ms
Transfer0 KB
Monthly Cost€14/mo
cdn.quantummetric.com
Other
Costly
Execution1146ms
Transfer144 KB
Unused38%
Monthly Cost€12/mo
sb.monetate.net
Other
Costly
Execution976ms
Transfer14 KB
Monthly Cost€11/mo
www.iberia.com
Other
Costly
Execution955ms
Transfer71 KB
Unused54%
Monthly Cost€10/mo
www.iberia.com
Other
Costly
Execution758ms
Transfer1 KB
Unused21%
Monthly Cost€8/mo
www.iberia.com
Other
Costly
Execution749ms
Transfer91 KB
Unused63%
Monthly Cost€8/mo
Google Tag Manager
Tag Manager
Costly
Execution632ms
Transfer170 KB
Unused29%
Monthly Cost€7/mo
euob.forroundprince.com
Other
Costly
Execution557ms
Transfer45 KB
Monthly Cost€6/mo
sb.monetate.net
Other
Costly
Execution480ms
Transfer2 KB
Monthly Cost€5/mo
Google Tag Manager
Tag Manager
Costly
Execution387ms
Transfer164 KB
Unused39%
Monthly Cost€4/mo
Google Tag Manager
Tag Manager
Costly
Execution306ms
Transfer193 KB
Unused31%
Monthly Cost€3/mo
sb.monetate.net
Other
Costly
Execution289ms
Transfer2 KB
Monthly Cost€3/mo
www.iberia.com
Other
Costly
Execution244ms
Transfer213 KB
Unused61%
Monthly Cost€3/mo
Google Tag Manager
Tag Manager
Costly
Execution209ms
Transfer144 KB
Unused49%
Monthly Cost€2/mo
obseu.forroundprince.com
Other
Optional
Execution179ms
Transfer2 KB
Monthly Cost€2/mo
Google Tag Manager
Tag Manager
Optional
Execution168ms
Transfer130 KB
Unused50%
Monthly Cost€2/mo
se.monetate.net
Other
Optional
Execution166ms
Transfer65 KB
Unused68%
Monthly Cost€2/mo
sb.monetate.net
Other
Optional
Execution154ms
Transfer7 KB
Monthly Cost€2/mo
sb.monetate.net
Other
Optional
Execution150ms
Transfer4 KB
Monthly Cost€2/mo
www.iberia.com
Other
Optional
Execution137ms
Transfer9 KB
Monthly Cost€1/mo
sdk.inbenta.io
Other
Optional
Execution136ms
Transfer150 KB
Unused70%
Monthly Cost€1/mo
cdn-ukwest.onetrust.com
Other
Optional
Execution129ms
Transfer9 KB
Monthly Cost€1/mo
www.iberia.com
Other
Optional
Execution92ms
Transfer40 KB
Monthly Cost€1/mo
www.iberia.com
Other
Optional
Execution82ms
Transfer42 KB
Monthly Cost€1/mo
af.monetate.net
Other
Optional
Execution82ms
Transfer3 KB
Monthly Cost€1/mo
cdn-ukwest.onetrust.com
Other
Optional
Execution64ms
Transfer94 KB
Unused53%
Monthly Cost€1/mo
Bing UET
Advertising
Optional
Execution57ms
Transfer16 KB
Monthly Cost€1/mo
sb.monetate.net
Other
Optional
Execution55ms
Transfer5 KB
Monthly Cost€1/mo
www.iberia.com
Other
Optional
Execution51ms
Transfer0 KB
Monthly Cost€1/mo
These scripts may cost more than they're worth
www.iberia.com adds 2494ms and costs ~€27/month
www.iberia.com adds 1940ms and costs ~€21/month
www.iberia.com adds 1469ms and costs ~€16/month
www.iberia.com adds 1287ms and costs ~€14/month
www.iberia.com adds 1268ms and costs ~€14/month
Unattributable adds 1258ms and costs ~€14/month
cdn.quantummetric.com adds 1146ms and costs ~€12/month
sb.monetate.net adds 976ms and costs ~€11/month
www.iberia.com adds 955ms and costs ~€10/month
www.iberia.com adds 758ms and costs ~€8/month
www.iberia.com adds 749ms and costs ~€8/month
Google Tag Manager adds 632ms and costs ~€7/month
euob.forroundprince.com adds 557ms and costs ~€6/month
sb.monetate.net adds 480ms and costs ~€5/month
Google Tag Manager adds 387ms and costs ~€4/month
Google Tag Manager adds 306ms and costs ~€3/month
sb.monetate.net adds 289ms and costs ~€3/month
www.iberia.com adds 244ms and costs ~€3/month
Google Tag Manager adds 209ms 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.iberia.com takes 2494ms 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
78% of www.iberia.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
www.iberia.com takes 1940ms 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.iberia.com takes 1469ms 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.iberia.com takes 1287ms 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
80% of www.iberia.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
www.iberia.com takes 1268ms 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 1258ms 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
cdn.quantummetric.com takes 1146ms 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
sb.monetate.net takes 976ms 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.iberia.com takes 955ms 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
54% of www.iberia.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
www.iberia.com takes 758ms 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.iberia.com takes 749ms 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 www.iberia.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
Google Tag Manager takes 632ms 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
euob.forroundprince.com takes 557ms 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
sb.monetate.net takes 480ms 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 387ms 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 306ms 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
sb.monetate.net takes 289ms 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.iberia.com takes 244ms 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
61% of www.iberia.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
Google Tag Manager takes 209ms 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
68% of se.monetate.net'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
70% of sdk.inbenta.io'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
53% of cdn-ukwest.onetrust.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.