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
46 images, 0 KB saveable
REVIEW
46 images, 0 KB saveable
Warning::
!
https://i.discogs.com/mnED8n3D92rYrHxNekNPXg7ISvFL... is missing width/height — may cause layout shift
Set explicit width and height to prevent CLS.
Warning::
!
https://i.discogs.com/gxXefTk9i3rNDJCeQsGS8KKw28aY... is missing width/height — may cause layout shift
Set explicit width and height to prevent CLS.
Warning::
!
https://i.discogs.com/jkcr-JFQkbkDb2y6T-a2OJunee2x... is missing width/height — may cause layout shift
Set explicit width and height to prevent CLS.
Warning::
!
https://i.discogs.com/RiHFanYu8un0NZbymNy2-eiUngJn... is missing width/height — may cause layout shift
Set explicit width and height to prevent CLS.
Warning::
!
https://i.discogs.com/wSNSu2i7-kxhH0CQg6c7UaFuVGA0... is missing width/height — may cause layout shift
Set explicit width and height to prevent CLS.
Warning::
!
https://i.discogs.com/jHzkxDFANvICNa7nT2v6CFoaAJeB... is missing width/height — may cause layout shift
Set explicit width and height to prevent CLS.
Warning::
!
https://i.discogs.com/gIOZyEg_GGACGXrWJnCoqUZ4U6te... is missing width/height — may cause layout shift
Set explicit width and height to prevent CLS.
Warning::
!
https://i.discogs.com/SOQrUtJxIXADZjLpNDz8nLES7qoO... is missing width/height — may cause layout shift
Set explicit width and height to prevent CLS.
Warning::
!
https://content.discogs.com/media/Pink-Floyd-%E2%8... is missing width/height — may cause layout shift
Set explicit width and height to prevent CLS.
Warning::
!
https://i.discogs.com/BLQ6KVpmEdw-ssXnwKIRbBMWeKF8... is missing width/height — may cause layout shift
Set explicit width and height to prevent CLS.
Warning::
!
https://i.discogs.com/3K4TUOXszHIhKNluabPmjFhfcZG9... is missing width/height — may cause layout shift
Set explicit width and height to prevent CLS.
Warning::
!
https://i.discogs.com/iwJF6BQKB2fCiFz8-Cf1akf8YqQG... is missing width/height — may cause layout shift
Set explicit width and height to prevent CLS.
Warning::
!
https://content.discogs.com/media/Damon-%E2%80%8E%... 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://content.discogs.com/media/Led-Zeppelin-%E2... is missing width/height — may cause layout shift
Set explicit width and height to prevent CLS.
Warning::
!
https://www.discogs.com/images/app/app-store-badge... is missing width/height — may cause layout shift
Set explicit width and height to prevent CLS.
Warning::
!
https://i.discogs.com/zOgtMSUgk4IG7FfrSf7X-EOu8yip... is missing width/height — may cause layout shift
Set explicit width and height to prevent CLS.
Warning::
!
https://i.discogs.com/Xxe3VyCsCkLovz-oZRyd9NiF_Umw... is missing width/height — may cause layout shift
Set explicit width and height to prevent CLS.
Warning::
!
https://i.discogs.com/423t7sOn1GBXqQR4dyx-4i45srVb... is missing width/height — may cause layout shift
Set explicit width and height to prevent CLS.
Warning::
!
https://content.discogs.com/media/Album-Cover-Mass... is missing width/height — may cause layout shift
Set explicit width and height to prevent CLS.
Warning::
!
https://i.discogs.com/i5V6zwzZbA_AZRCrstIm9BdL_BQi... is missing width/height — may cause layout shift
Set explicit width and height to prevent CLS.
Warning::
!
https://i.discogs.com/9gWwB4po4W4M9zUN1zHnQ5FtMQvI... is missing width/height — may cause layout shift
Set explicit width and height to prevent CLS.
Warning::
!
https://i.discogs.com/uwaqwB1edChQLqu679sYivUtw1nS... is missing width/height — may cause layout shift
Set explicit width and height to prevent CLS.
Warning::
!
https://i.discogs.com/AgZP2lCSUqTFvzB8SARbIXl5p2Dz... is missing width/height — may cause layout shift
Set explicit width and height to prevent CLS.
Warning::
!
https://content.discogs.com/media/Mayhem-Deathcrus... is missing width/height — may cause layout shift
Set explicit width and height to prevent CLS.
Warning::
!
https://i.discogs.com/KlxOi0a2b5CA-pZdmSV7vRZRQSOx... is missing width/height — may cause layout shift
Set explicit width and height to prevent CLS.
Warning::
!
https://i.discogs.com/n-O2orc5xv_n-s3j_OfHVVRpot8R... is missing width/height — may cause layout shift
Set explicit width and height to prevent CLS.
Warning::
!
https://i.discogs.com/H4JA-hGmgxKZL37yOIGusoVjHWZm... is missing width/height — may cause layout shift
Set explicit width and height to prevent CLS.
Warning::
!
https://i.discogs.com/TW0qo0lvx7GEPg1oliGUc6SMZuze... is missing width/height — may cause layout shift
Set explicit width and height to prevent CLS.
Warning::
!
https://i.discogs.com/Q_b6zmCmoHj4IcKoH9Zcc1pUUc2q... is missing width/height — may cause layout shift
Set explicit width and height to prevent CLS.
Warning::
!
https://content.discogs.com/media/Tina-Brooks-%E2%... is missing width/height — may cause layout shift
Set explicit width and height to prevent CLS.
Warning::
!
https://www.discogs.com/images/app/google-play-bad... is missing width/height — may cause layout shift
Set explicit width and height to prevent CLS.
Warning::
!
https://i.discogs.com/ei75ol-bEK3-KlHlc72ulSBCXa5i... is missing width/height — may cause layout shift
Set explicit width and height to prevent CLS.
Warning::
!
https://i.discogs.com/oJ5kyZIEGfrYSGESjFtoGDxfJKQA... is missing width/height — may cause layout shift
Set explicit width and height to prevent CLS.
Warning::
!
https://i.discogs.com/X7WkoOJa5TrLoJng72jh8ZSyj5X1... is missing width/height — may cause layout shift
Set explicit width and height to prevent CLS.
Warning::
!
https://i.discogs.com/gykH4wDnrpdxL9D8HCQhnj2-YP0e... is missing width/height — may cause layout shift
Set explicit width and height to prevent CLS.
46images3.8 MB
0oversized-0 KB
45legacy format
36missing 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
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
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
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
No web fonts (system fonts)
PASS
No web fonts (system fonts)
Info::
✓
No web fonts loaded — system fonts are fastest
No web fonts loaded — system fonts are optimal.
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
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
106 requests over 4363ms
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-party5353ms · 1380KB · $71/mo
Script
Category
Execution
Transfer
Unused
Monthly Cost
Verdict
Unattributable
Unattributable
Other
1610ms
0 KB
—
$21/mo
Costly
www.discogs.com
www.discogs.com
Other
693ms
34 KB
—
$9/mo
Costly
Google Tag Manager
www.googletagmanager.com
Tag Manager
597ms
184 KB
38%
$8/mo
Costly
OneTrust
cdn.cookielaw.org
Consent
533ms
126 KB
57%
$7/mo
Essential
cdn-4.convertexperiments.com
cdn-4.convertexperiments.com
Other
287ms
54 KB
54%
$4/mo
Costly
Facebook Pixel
connect.facebook.net
Advertising
255ms
131 KB
38%
$3/mo
Costly
jsDelivr
cdn.jsdelivr.net
CDN
228ms
39 KB
63%
$3/mo
Costly
Google Tag Manager
www.googletagmanager.com
Tag Manager
227ms
160 KB
48%
$3/mo
Costly
st.discogs.com
st.discogs.com
Other
207ms
81 KB
60%
$3/mo
Costly
st.discogs.com
st.discogs.com
Other
157ms
76 KB
62%
$2/mo
Optional
Facebook Pixel
connect.facebook.net
Advertising
136ms
96 KB
44%
$2/mo
Optional
www.discogs.com
www.discogs.com
Other
106ms
58 KB
47%
$1/mo
Optional
www.discogs.com
www.discogs.com
Other
105ms
263 KB
78%
$1/mo
Optional
www.discogs.com
www.discogs.com
Other
78ms
56 KB
44%
$1/mo
Optional
OneTrust
cdn.cookielaw.org
Consent
68ms
9 KB
—
$1/mo
Essential
static.cloudflareinsights.com
static.cloudflareinsights.com
Other
67ms
11 KB
—
$1/mo
Optional
Unattributable
Other
Costly
Execution1610ms
Transfer0 KB
Monthly Cost$21/mo
www.discogs.com
Other
Costly
Execution693ms
Transfer34 KB
Monthly Cost$9/mo
Google Tag Manager
Tag Manager
Costly
Execution597ms
Transfer184 KB
Unused38%
Monthly Cost$8/mo
OneTrust
Consent
Essential
Execution533ms
Transfer126 KB
Unused57%
Monthly Cost$7/mo
cdn-4.convertexperiments.com
Other
Costly
Execution287ms
Transfer54 KB
Unused54%
Monthly Cost$4/mo
Facebook Pixel
Advertising
Costly
Execution255ms
Transfer131 KB
Unused38%
Monthly Cost$3/mo
jsDelivr
CDN
Costly
Execution228ms
Transfer39 KB
Unused63%
Monthly Cost$3/mo
Google Tag Manager
Tag Manager
Costly
Execution227ms
Transfer160 KB
Unused48%
Monthly Cost$3/mo
st.discogs.com
Other
Costly
Execution207ms
Transfer81 KB
Unused60%
Monthly Cost$3/mo
st.discogs.com
Other
Optional
Execution157ms
Transfer76 KB
Unused62%
Monthly Cost$2/mo
Facebook Pixel
Advertising
Optional
Execution136ms
Transfer96 KB
Unused44%
Monthly Cost$2/mo
www.discogs.com
Other
Optional
Execution106ms
Transfer58 KB
Unused47%
Monthly Cost$1/mo
www.discogs.com
Other
Optional
Execution105ms
Transfer263 KB
Unused78%
Monthly Cost$1/mo
www.discogs.com
Other
Optional
Execution78ms
Transfer56 KB
Unused44%
Monthly Cost$1/mo
OneTrust
Consent
Essential
Execution68ms
Transfer9 KB
Monthly Cost$1/mo
static.cloudflareinsights.com
Other
Optional
Execution67ms
Transfer11 KB
Monthly Cost$1/mo
These scripts may cost more than they're worth
Unattributable adds 1610ms and costs ~$21/month
www.discogs.com adds 693ms and costs ~$9/month
Google Tag Manager adds 597ms and costs ~$8/month
cdn-4.convertexperiments.com adds 287ms and costs ~$4/month
Facebook Pixel adds 255ms and costs ~$3/month
jsDelivr adds 228ms and costs ~$3/month
Google Tag Manager adds 227ms and costs ~$3/month
st.discogs.com adds 207ms and costs ~$3/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
Unattributable takes 1610ms 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.discogs.com takes 693ms 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 597ms 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
57% 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
cdn-4.convertexperiments.com takes 287ms 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 cdn-4.convertexperiments.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
Facebook Pixel takes 255ms 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
jsDelivr 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
63% of jsDelivr'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 227ms 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
st.discogs.com takes 207ms 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
60% of st.discogs.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
62% of st.discogs.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
78% of www.discogs.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.
400 ms
800 ms
1.6 s
2.0 s
2.4 s
3.2 s