Skip to content
https://copernicus.org

Performance

· 15 checks — Lighthouse + waterfall + sustainability rolled into one auditable list.
SCORE
89
GRADE
B
FIX
2
REVIEW
2
PASS
9
INFO
2

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

Mobile Desktop
95
Performance Overall performance score (0–100) based on Core Web Vitals and other metrics. 90+ is good.
63
Accessibility Measures how accessible the page is for users with disabilities. Checks color contrast, ARIA labels, and semantic HTML.
88
Best Practices Checks for modern web development best practices including HTTPS, no console errors, and secure JavaScript.
75
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.

1.02 s

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

1.29 s

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

0 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.

1.02 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.

1.29 s

Page Load Progression

375 ms
750 ms
1.1 s
1.5 s
1.9 s
2.2 s
2.6 s
3.0 s
Checks
15
9 PASS 2 REVIEW 2 FIX
D
Third-Party Impact
Action
99% third-party, 0 ms blocking
FIX
99% third-party, 0 ms blocking
Warning::
Third-party code accounts for 99% of page weight (688.1 KiB of 694.9 KiB)
Info::
Third-party blocking time is low (0 ms)
99%
First-party Third-party
D
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.
Info::
ETag present — enables conditional (304) responses
Info::
Last-Modified header present

No Cache-Control header

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

C
Image Optimization
Action
13 images, 0 KB saveable
REVIEW
13 images, 0 KB saveable
Warning::
https://www.copernicus.org/graphic_grey_right_symb... is missing width/height — may cause layout shift
Set explicit width and height to prevent CLS.
Warning::
https://www.copernicus.org/Logo-Western-University... is missing width/height — may cause layout shift
Set explicit width and height to prevent CLS.
Warning::
https://www.copernicus.org/logo-deutschlandstipend... is missing width/height — may cause layout shift
Set explicit width and height to prevent CLS.
Warning::
https://www.copernicus.org/ci_refresh_graphic_cc_b... is missing width/height — may cause layout shift
Set explicit width and height to prevent CLS.
Warning::
https://www.copernicus.org/image-icon-rocket.png is missing width/height — may cause layout shift
Set explicit width and height to prevent CLS.
Warning::
https://www.copernicus.org/image_orcid_logo.jpg is missing width/height — may cause layout shift
Set explicit width and height to prevent CLS.
Warning::
https://www.copernicus.org/graphic-copernicus-meda... is missing width/height — may cause layout shift
Set explicit width and height to prevent CLS.
13 images 377 KB
0 oversized -0 KB
13 legacy format
7 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

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

Green Hosting

No green hosting detected

A+
Page Weight Budget
695 KB transferred, 48 requests
PASS
695 KB transferred, 48 requests
Info::
Page weighs 1.4 MB (695 KB transferred)
Info::
48 HTTP requests
Info::
Estimated 0.14 g CO2 per page load
695 KB / 2.4 MB budget
695 KB transferred
48 requests
0.14 g CO2 per page load
Images 376.7 KiB 54%
Fonts 100.0 KiB 14%
CSS 93.2 KiB 13%
JavaScript 73.3 KiB 11%
Other 44.8 KiB 6%
HTML 6.9 KiB 1%
0 2.4 MB 4.9 MB
Under budget
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+
JS Execution Cost
127ms total JS execution
PASS
127ms total JS execution
Info::
Unattributable: 72ms CPU time
Info::
https://copernicus.org/: 54ms CPU time
Warning::
Third-party scripts: 72ms (57% of total)

Main Thread Breakdown

Other 49% Style & Layout 17% Script Evaluation 17% Parse HTML & CSS 10% Script Parsing & Compilation 4% Rendering 4%
ScriptTotalScriptingParse/CompileParty
Unattributable72ms1ms0ms3rd
https://copernicus.org/54ms1ms0ms1st
A+
Font Loading
2 fonts (100 KB)
PASS
2 fonts (100 KB)
Info::
2 font(s) use font-display: swap (FOUT risk but functional)

Web fonts

2

100 KB total

Render-blocking

0

of 2

Dominant font-display

swap

Most common across fonts

Font loading timeline
Transfer FOIT (block) FOUT (swap)
0 ms 500 ms 1.0 s FCP 1.0 s LCP 1.3 sdata:application/x-font-ttf;charset=utf-8;base64,AAEAAAALAIAAAwAwT1MvMg8SDpMAAAC8AAAAYGNtYXDxl8QZAA…x-font-ttf;charset=utf-... data:application/x-font-ttf;charset=utf-8;base64,AAEAAAALAIAAAwAwT1MvMg8SDpMAAAC8AAAAYGNtYXDxl8QZAA… — 2.7 KiB — 24 ms — font-display: swaphttps://cdn.copernicus.org/fonts/FontAwesome/4.7.0/fontawesome-webfont.ttf?v=4.7.0fontawesome-webfont.ttf https://cdn.copernicus.org/fonts/FontAwesome/4.7.0/fontawesome-webfont.ttf?v=4.7.0 — 97.3 KiB — 13 ms — font-display: swap
x-font-ttf;charset=utf-... unknown swap
Size 3 KB
Load time 24 ms
Start 278 ms
Risk FOUT — text flashes from fallback to web font
fontawesome-webfont.ttf unknown swap
Size 97 KB
Load time 13 ms
Start 298 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 ~30 KB and ~60 ms

A+
JS Bundles
11 scripts, 20 KB unused
PASS
11 scripts, 20 KB unused
Warning::
https://cdn.copernicus.org/libraries/jquery/1.11.1...: 20 KB unused (62%)
Consider code splitting or tree shaking to reduce unused code.
Info::
Total unused JavaScript: 20 KB
20 KB unused JavaScript

Downloaded but never executed on this page.

ScriptSizeUnusedMinifiedParty
https://cdn.copernicus.org/libraries/jquery/1.11.1/jquery.min.js33 KB20 KB (62%)✓3rd
https://cdn.copernicus.org/js/copernicus.min.js5 KB—✓3rd
https://cdn.copernicus.org/libraries/bootstrap/current/js/popper.js8 KB—✓3rd
https://cdn.copernicus.org/libraries/bootstrap/current/js/bootstrap.min.js15 KB—✓3rd
https://www.copernicus.org/co_common.js4 KB—✓3rd
https://www.copernicus.org/onload_javascript_actions.js1 KB—✓3rd
https://www.copernicus.org/template_copernicus_common.js2 KB—✓3rd
https://www.copernicus.org/template-responsive.js2 KB—✓3rd
https://www.copernicus.org/ci_refresh_jquery_slides_min.js3 KB—✓3rd
https://www.copernicus.org/ci_refresh_jquery_slider.js1 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

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
Page Weight Inventory
48 resources · 695 KB · 20 KB savings available
PASS
48 resources · 695 KB · 20 KB savings available
Info::
Within 1MB page-weight target
Got: 695 KB
Warning::
47 third-party resources (99% of weight)
48 resources · 694.9 KiB · 47 third-party Within 1MB page-weight target
Image 61% · 421.6 KiB
Font 14% · 100.0 KiB
CSS 13% · 93.2 KiB
JavaScript 11% · 73.3 KiB
Document 1% · 6.9 KiB

~20.2 KiB of savings available

Remove unused JavaScript: 20.2 KiB
Network Waterfall
48 requests over 811ms
INFO
0 ms 500 ms 1.0 s FCP 1.0 s LCP 1.3 shttps://copernicus.org// https://copernicus.org/ — 200 — 6.9 KiB — 102 ms — http/1.1https://cdn.copernicus.org/libraries/jquery/1.11.1/jquery.min.jscdn.copernicus.org/libraries/jquery... https://cdn.copernicus.org/libraries/jquery/1.11.1/jquery.min.js — 200 — 33.4 KiB — 40 ms — http/1.1https://cdn.copernicus.org/js/copernicus.min.jscdn.copernicus.org/js/copernicus.mi... https://cdn.copernicus.org/js/copernicus.min.js — 200 — 5.0 KiB — 34 ms — http/1.1https://cdn.copernicus.org/libraries/bootstrap/current/css/bootstrap.min.csscdn.copernicus.org/libraries/bootst... https://cdn.copernicus.org/libraries/bootstrap/current/css/bootstrap.min.css — 200 — 24.1 KiB — 27 ms — http/1.1https://cdn.copernicus.org/libraries/bootstrap/current/css/bootstrap-media.min.csscdn.copernicus.org/libraries/bootst... https://cdn.copernicus.org/libraries/bootstrap/current/css/bootstrap-media.min.css — 200 — 6.9 KiB — 27 ms — http/1.1https://cdn.copernicus.org/libraries/bootstrap/current/css/bootstrap-grid.min.csscdn.copernicus.org/libraries/bootst... https://cdn.copernicus.org/libraries/bootstrap/current/css/bootstrap-grid.min.css — 200 — 6.4 KiB — 27 ms — http/1.1https://cdn.copernicus.org/libraries/bootstrap/current/css/bootstrap-reboot.min.csscdn.copernicus.org/libraries/bootst... https://cdn.copernicus.org/libraries/bootstrap/current/css/bootstrap-reboot.min.css — 200 — 2.1 KiB — 19 ms — http/1.1https://cdn.copernicus.org/libraries/bootstrap/current/js/popper.jscdn.copernicus.org/libraries/bootst... https://cdn.copernicus.org/libraries/bootstrap/current/js/popper.js — 200 — 7.7 KiB — 40 ms — http/1.1https://cdn.copernicus.org/libraries/bootstrap/current/js/bootstrap.min.jscdn.copernicus.org/libraries/bootst... https://cdn.copernicus.org/libraries/bootstrap/current/js/bootstrap.min.js — 200 — 15.3 KiB — 40 ms — http/1.1https://cdn.copernicus.org/libraries/unsemantic/unsemantic.min.csscdn.copernicus.org/libraries/unsema... https://cdn.copernicus.org/libraries/unsemantic/unsemantic.min.css — 200 — 4.5 KiB — 25 ms — http/1.1https://cdn.copernicus.org/css/copernicus-min.csscdn.copernicus.org/css/copernicus-m... https://cdn.copernicus.org/css/copernicus-min.css — 200 — 3.9 KiB — 23 ms — http/1.1https://cdn.copernicus.org/css/fontawesome.csscdn.copernicus.org/css/fontawesome.... https://cdn.copernicus.org/css/fontawesome.css — 200 — 1.3 KiB — 27 ms — http/1.1https://cdn.copernicus.org/fonts/FontAwesome/5.11.2_and_4.7.0/css/all.font.csscdn.copernicus.org/fonts/FontAwesom... https://cdn.copernicus.org/fonts/FontAwesome/5.11.2_and_4.7.0/css/all.font.css — 200 — 31.3 KiB — 34 ms — http/1.1https://www.copernicus.org/template-style-social-icon.csswww.copernicus.org/template-style-s... https://www.copernicus.org/template-style-social-icon.css — 200 — 5.3 KiB — 111 ms — http/1.1https://www.copernicus.org/template_base_2019.csswww.copernicus.org/template_base_20... https://www.copernicus.org/template_base_2019.css — 200 — 6.7 KiB — 111 ms — http/1.1https://www.copernicus.org/co_common.jswww.copernicus.org/co_common.js https://www.copernicus.org/co_common.js — 200 — 3.5 KiB — 110 ms — http/1.1https://www.copernicus.org/onload_javascript_actions.jswww.copernicus.org/onload_javascrip... https://www.copernicus.org/onload_javascript_actions.js — 200 — 576 B — 110 ms — http/1.1https://www.copernicus.org/template_copernicus_common.jswww.copernicus.org/template_coperni... https://www.copernicus.org/template_copernicus_common.js — 200 — 1.7 KiB — 149 ms — http/1.1https://www.copernicus.org/template-responsive.jswww.copernicus.org/template-respons... https://www.copernicus.org/template-responsive.js — 200 — 1.7 KiB — 149 ms — http/1.1https://www.copernicus.org/ci_refresh_jquery_slides_min.jswww.copernicus.org/ci_refresh_jquer... https://www.copernicus.org/ci_refresh_jquery_slides_min.js — 200 — 3.2 KiB — 149 ms — http/1.1https://www.copernicus.org/ci_refresh_jquery_slider.jswww.copernicus.org/ci_refresh_jquer... https://www.copernicus.org/ci_refresh_jquery_slider.js — 200 — 518 B — 108 ms — http/1.1https://www.copernicus.org/template_counter.jswww.copernicus.org/template_counter... https://www.copernicus.org/template_counter.js — 200 — 714 B — 108 ms — http/1.1https://www.copernicus.org/ci_refresh_header_org.jpgwww.copernicus.org/ci_refresh_heade... https://www.copernicus.org/ci_refresh_header_org.jpg — 200 — 98.3 KiB — 103 ms — http/1.1https://www.copernicus.org/image_orcid_logo.jpgwww.copernicus.org/image_orcid_logo... https://www.copernicus.org/image_orcid_logo.jpg — 200 — 19.7 KiB — 39 ms — http/1.1https://www.copernicus.org/logo-deutschlandstipendium-130px.jpgwww.copernicus.org/logo-deutschland... https://www.copernicus.org/logo-deutschlandstipendium-130px.jpg — 200 — 25.4 KiB — 36 ms — http/1.1https://www.copernicus.org/ci_refresh_graphic_cc_by_footer_logo.jpgwww.copernicus.org/ci_refresh_graph... https://www.copernicus.org/ci_refresh_graphic_cc_by_footer_logo.jpg — 200 — 15.5 KiB — 67 ms — http/1.1https://www.copernicus.org/ci_refresh_graphic_topas_logo.jpgwww.copernicus.org/ci_refresh_graph... https://www.copernicus.org/ci_refresh_graphic_topas_logo.jpg — 200 — 6.4 KiB — 36 ms — http/1.1https://www.copernicus.org/image-icon-rocket.pngwww.copernicus.org/image-icon-rocke... https://www.copernicus.org/image-icon-rocket.png — 200 — 2.1 KiB — 38 ms — http/1.1https://www.copernicus.org/graphic-copernicus-medallist-2026-ben-poulter-80x80.jpgwww.copernicus.org/graphic-copernic... https://www.copernicus.org/graphic-copernicus-medallist-2026-ben-poulter-80x80.jpg — 200 — 23.5 KiB — 67 ms — http/1.1data:application/x-font-ttf;charset=utf-8;base64,AAEAAAALAIAAAwAwT1MvMg8SDpMAAAC8AAAAYGNtYXDxl8QZAA…data:application/x-font-ttf;charset... data:application/x-font-ttf;charset=utf-8;base64,AAEAAAALAIAAAwAwT1MvMg8SDpMAAAC8AAAAYGNtYXDxl8QZAA… — 200 — 2.7 KiB — 24 ms — data
0 ms 500 ms 1.0 s FCP 1.0 s LCP 1.3 shttps://copernicus.org// https://copernicus.org/ — 200 — 6.9 KiB — 102 ms — http/1.1https://cdn.copernicus.org/libraries/jquery/1.11.1/jquery.min.jscdn.copernicus.org/libraries/jquery... https://cdn.copernicus.org/libraries/jquery/1.11.1/jquery.min.js — 200 — 33.4 KiB — 40 ms — http/1.1https://cdn.copernicus.org/js/copernicus.min.jscdn.copernicus.org/js/copernicus.mi... https://cdn.copernicus.org/js/copernicus.min.js — 200 — 5.0 KiB — 34 ms — http/1.1https://cdn.copernicus.org/libraries/bootstrap/current/css/bootstrap.min.csscdn.copernicus.org/libraries/bootst... https://cdn.copernicus.org/libraries/bootstrap/current/css/bootstrap.min.css — 200 — 24.1 KiB — 27 ms — http/1.1https://cdn.copernicus.org/libraries/bootstrap/current/css/bootstrap-media.min.csscdn.copernicus.org/libraries/bootst... https://cdn.copernicus.org/libraries/bootstrap/current/css/bootstrap-media.min.css — 200 — 6.9 KiB — 27 ms — http/1.1https://cdn.copernicus.org/libraries/bootstrap/current/css/bootstrap-grid.min.csscdn.copernicus.org/libraries/bootst... https://cdn.copernicus.org/libraries/bootstrap/current/css/bootstrap-grid.min.css — 200 — 6.4 KiB — 27 ms — http/1.1https://cdn.copernicus.org/libraries/bootstrap/current/css/bootstrap-reboot.min.csscdn.copernicus.org/libraries/bootst... https://cdn.copernicus.org/libraries/bootstrap/current/css/bootstrap-reboot.min.css — 200 — 2.1 KiB — 19 ms — http/1.1https://cdn.copernicus.org/libraries/bootstrap/current/js/popper.jscdn.copernicus.org/libraries/bootst... https://cdn.copernicus.org/libraries/bootstrap/current/js/popper.js — 200 — 7.7 KiB — 40 ms — http/1.1https://cdn.copernicus.org/libraries/bootstrap/current/js/bootstrap.min.jscdn.copernicus.org/libraries/bootst... https://cdn.copernicus.org/libraries/bootstrap/current/js/bootstrap.min.js — 200 — 15.3 KiB — 40 ms — http/1.1https://cdn.copernicus.org/libraries/unsemantic/unsemantic.min.csscdn.copernicus.org/libraries/unsema... https://cdn.copernicus.org/libraries/unsemantic/unsemantic.min.css — 200 — 4.5 KiB — 25 ms — http/1.1https://cdn.copernicus.org/css/copernicus-min.csscdn.copernicus.org/css/copernicus-m... https://cdn.copernicus.org/css/copernicus-min.css — 200 — 3.9 KiB — 23 ms — http/1.1https://cdn.copernicus.org/css/fontawesome.csscdn.copernicus.org/css/fontawesome.... https://cdn.copernicus.org/css/fontawesome.css — 200 — 1.3 KiB — 27 ms — http/1.1https://cdn.copernicus.org/fonts/FontAwesome/5.11.2_and_4.7.0/css/all.font.csscdn.copernicus.org/fonts/FontAwesom... https://cdn.copernicus.org/fonts/FontAwesome/5.11.2_and_4.7.0/css/all.font.css — 200 — 31.3 KiB — 34 ms — http/1.1https://www.copernicus.org/template-style-social-icon.csswww.copernicus.org/template-style-s... https://www.copernicus.org/template-style-social-icon.css — 200 — 5.3 KiB — 111 ms — http/1.1https://www.copernicus.org/template_base_2019.csswww.copernicus.org/template_base_20... https://www.copernicus.org/template_base_2019.css — 200 — 6.7 KiB — 111 ms — http/1.1https://www.copernicus.org/co_common.jswww.copernicus.org/co_common.js https://www.copernicus.org/co_common.js — 200 — 3.5 KiB — 110 ms — http/1.1https://www.copernicus.org/onload_javascript_actions.jswww.copernicus.org/onload_javascrip... https://www.copernicus.org/onload_javascript_actions.js — 200 — 576 B — 110 ms — http/1.1https://www.copernicus.org/template_copernicus_common.jswww.copernicus.org/template_coperni... https://www.copernicus.org/template_copernicus_common.js — 200 — 1.7 KiB — 149 ms — http/1.1https://www.copernicus.org/template-responsive.jswww.copernicus.org/template-respons... https://www.copernicus.org/template-responsive.js — 200 — 1.7 KiB — 149 ms — http/1.1https://www.copernicus.org/ci_refresh_jquery_slides_min.jswww.copernicus.org/ci_refresh_jquer... https://www.copernicus.org/ci_refresh_jquery_slides_min.js — 200 — 3.2 KiB — 149 ms — http/1.1https://www.copernicus.org/ci_refresh_jquery_slider.jswww.copernicus.org/ci_refresh_jquer... https://www.copernicus.org/ci_refresh_jquery_slider.js — 200 — 518 B — 108 ms — http/1.1https://www.copernicus.org/template_counter.jswww.copernicus.org/template_counter... https://www.copernicus.org/template_counter.js — 200 — 714 B — 108 ms — http/1.1https://www.copernicus.org/ci_refresh_header_org.jpgwww.copernicus.org/ci_refresh_heade... https://www.copernicus.org/ci_refresh_header_org.jpg — 200 — 98.3 KiB — 103 ms — http/1.1https://www.copernicus.org/image_orcid_logo.jpgwww.copernicus.org/image_orcid_logo... https://www.copernicus.org/image_orcid_logo.jpg — 200 — 19.7 KiB — 39 ms — http/1.1https://www.copernicus.org/logo-deutschlandstipendium-130px.jpgwww.copernicus.org/logo-deutschland... https://www.copernicus.org/logo-deutschlandstipendium-130px.jpg — 200 — 25.4 KiB — 36 ms — http/1.1https://www.copernicus.org/ci_refresh_graphic_cc_by_footer_logo.jpgwww.copernicus.org/ci_refresh_graph... https://www.copernicus.org/ci_refresh_graphic_cc_by_footer_logo.jpg — 200 — 15.5 KiB — 67 ms — http/1.1https://www.copernicus.org/ci_refresh_graphic_topas_logo.jpgwww.copernicus.org/ci_refresh_graph... https://www.copernicus.org/ci_refresh_graphic_topas_logo.jpg — 200 — 6.4 KiB — 36 ms — http/1.1https://www.copernicus.org/image-icon-rocket.pngwww.copernicus.org/image-icon-rocke... https://www.copernicus.org/image-icon-rocket.png — 200 — 2.1 KiB — 38 ms — http/1.1https://www.copernicus.org/graphic-copernicus-medallist-2026-ben-poulter-80x80.jpgwww.copernicus.org/graphic-copernic... https://www.copernicus.org/graphic-copernicus-medallist-2026-ben-poulter-80x80.jpg — 200 — 23.5 KiB — 67 ms — http/1.1data:application/x-font-ttf;charset=utf-8;base64,AAEAAAALAIAAAwAwT1MvMg8SDpMAAAC8AAAAYGNtYXDxl8QZAA…data:application/x-font-ttf;charset... data:application/x-font-ttf;charset=utf-8;base64,AAEAAAALAIAAAwAwT1MvMg8SDpMAAAC8AAAAYGNtYXDxl8QZAA… — 200 — 2.7 KiB — 24 ms — datahttps://www.copernicus.org/graphic_grey_right_symbol.pngwww.copernicus.org/graphic_grey_rig... https://www.copernicus.org/graphic_grey_right_symbol.png — 200 — 460 B — 47 ms — http/1.1https://www.copernicus.org/image_icon_our_identity.svgwww.copernicus.org/image_icon_our_i... https://www.copernicus.org/image_icon_our_identity.svg — 200 — 117.1 KiB — 147 ms — http/1.1https://www.copernicus.org/Logo-Western-University.svgwww.copernicus.org/Logo-Western-Uni... https://www.copernicus.org/Logo-Western-University.svg — 200 — 19.7 KiB — 84 ms — http/1.1https://cdn.copernicus.org/fonts/FontAwesome/4.7.0/fontawesome-webfont.ttf?v=4.7.0cdn.copernicus.org/fonts/FontAwesom... https://cdn.copernicus.org/fonts/FontAwesome/4.7.0/fontawesome-webfont.ttf?v=4.7.0 — 200 — 97.3 KiB — 13 ms — http/1.1https://www.copernicus.org/image_icon_our_mission.svgwww.copernicus.org/image_icon_our_m... https://www.copernicus.org/image_icon_our_mission.svg — 200 — 10.0 KiB — 34 ms — http/1.1https://www.copernicus.org/copernicus_stamp.svgwww.copernicus.org/copernicus_stamp... https://www.copernicus.org/copernicus_stamp.svg — 200 — 12.0 KiB — 35 ms — http/1.1https://www.copernicus.org/Graphic_Logo_Copernicus_ORG_RGB.svgwww.copernicus.org/Graphic_Logo_Cop... https://www.copernicus.org/Graphic_Logo_Copernicus_ORG_RGB.svg — 200 — 26.7 KiB — 34 ms — http/1.1https://www.copernicus.org/ci_refresh_print_css.csswww.copernicus.org/ci_refresh_print... https://www.copernicus.org/ci_refresh_print_css.css — 200 — 624 B — 35 ms — http/1.1https://www.copernicus.org/favicon_copernicus_96x96_.pngwww.copernicus.org/favicon_copernic... https://www.copernicus.org/favicon_copernicus_96x96_.png — 200 — 3.8 KiB — 34 ms — http/1.1https://www.copernicus.org/favicon_copernicus_128x128_.pngwww.copernicus.org/favicon_copernic... https://www.copernicus.org/favicon_copernicus_128x128_.png — 200 — 4.4 KiB — 34 ms — http/1.1https://www.copernicus.org/favicon_copernicus_196x196_.pngwww.copernicus.org/favicon_copernic... https://www.copernicus.org/favicon_copernicus_196x196_.png — 200 — 6.8 KiB — 34 ms — http/1.1https://www.copernicus.org/favicon_copernicus_195x195_.pngwww.copernicus.org/favicon_copernic... https://www.copernicus.org/favicon_copernicus_195x195_.png — 200 — 5.7 KiB — 34 ms — http/1.1https://www.copernicus.org/favicon_copernicus_228x228_.pngwww.copernicus.org/favicon_copernic... https://www.copernicus.org/favicon_copernicus_228x228_.png — 200 — 7.6 KiB — 34 ms — http/1.1https://www.copernicus.org/favicon_copernicus_64x64_.icowww.copernicus.org/favicon_copernic... https://www.copernicus.org/favicon_copernicus_64x64_.ico — 200 — 4.1 KiB — 34 ms — http/1.1https://www.copernicus.org/favicon_copernicus_48x48_.icowww.copernicus.org/favicon_copernic... https://www.copernicus.org/favicon_copernicus_48x48_.ico — 200 — 3.7 KiB — 34 ms — http/1.1https://www.copernicus.org/favicon_copernicus_32x32_.icowww.copernicus.org/favicon_copernic... https://www.copernicus.org/favicon_copernicus_32x32_.ico — 200 — 3.1 KiB — 34 ms — http/1.1https://www.copernicus.org/favicon_copernicus_24x24_.icowww.copernicus.org/favicon_copernic... https://www.copernicus.org/favicon_copernicus_24x24_.ico — 200 — 2.9 KiB — 34 ms — http/1.1https://www.copernicus.org/favicon_copernicus_16x16_.icowww.copernicus.org/favicon_copernic... https://www.copernicus.org/favicon_copernicus_16x16_.ico — 200 — 2.7 KiB — 34 ms — http/1.1
HTML JavaScript CSS Images Fonts XHR/Fetch Other
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 72ms · 0KB · €1/mo
Unattributable
Other
Optional
Execution 72ms
Transfer 0 KB
Monthly Cost €1/mo

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

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.

Send Feedback