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https://copernicus.org

Performance

· 17 checks — Lighthouse + waterfall + sustainability rolled into one auditable list.
SCORE
89
GRADE
B
FIX
2
REVIEW
3
PASS
10
INFO
2

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

Mobile Desktop
65
Performance Overall performance score (0–100) based on Core Web Vitals and other metrics. 90+ is good.
75
Accessibility Measures how accessible the page is for users with disabilities. Checks color contrast, ARIA labels, and semantic HTML.
85
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.

4.60 s

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

6.58 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.

0.000

Speed Index Speed Index — how quickly content is visually displayed during load. Under 3.4s is good.

4.60 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.

6.63 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
17
10 PASS 3 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 (849.9 KiB of 856.8 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/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/graphic-copernicus-meda... is missing width/height — may cause layout shift
Set explicit width and height to prevent CLS.
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.
13 images 377 KB
0 oversized -0 KB
13 legacy format
4 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

B
JS Execution Cost
579ms total JS execution
REVIEW
579ms total JS execution
Warning::
Unattributable: 298ms CPU time
Info::
https://cdn.copernicus.org/libraries/jquery/1.11.1...: 192ms CPU time
Info::
https://copernicus.org/: 89ms CPU time
Warning::
Third-party scripts: 490ms (85% of total)

Main Thread Breakdown

Other 50% Script Evaluation 19% Style & Layout 16% Parse HTML & CSS 9% Script Parsing & Compilation 3%
ScriptTotalScriptingParse/CompileParty
Unattributable298ms5ms0ms3rd
https://cdn.copernicus.org/libraries/jquery/1.11.1/jquery.min.js192ms88ms6ms3rd
https://copernicus.org/89ms3ms0ms1st
C
Green Hosting
Action
Whether the site is served from green-energy infrastructure
REVIEW

Green Hosting

No green hosting detected

A
Page Weight Budget
857 KB transferred, 49 requests
PASS
857 KB transferred, 49 requests
Info::
Page weighs 1.6 MB (857 KB transferred)
Info::
Fonts are 262 KB — consider subsetting or using system fonts
Subset fonts to include only used characters, or switch to system font stacks.
Got: 262 KB
Info::
49 HTTP requests
Info::
Estimated 0.18 g CO2 per page load
857 KB / 2.4 MB budget
857 KB transferred
49 requests
0.18 g CO2 per page load
Images 376.7 KiB 44%
Fonts 261.9 KiB 31%
CSS 93.2 KiB 11%
JavaScript 73.3 KiB 9%
Other 44.8 KiB 5%
HTML 6.9 KiB 1%
0 2.4 MB 4.9 MB
Under budget

Subset fonts to include only used characters, or switch to system font stacks.

Why this matters

Font payload is large — subset to used glyphs only, or fall back to system fonts (zero load time).

Source: web.dev font loading

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 (262 KB)
PASS
3 fonts (262 KB)
Info::
3 font(s) use font-display: swap (FOUT risk but functional)

Web fonts

3

262 KB total

Render-blocking

0

of 3

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 4.0 s 5.0 s 6.0 s FCP 4.6 s LCP 6.6 shttps://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 — 97.4 KiB — 60 ms — font-display: swaphttps://cdn.copernicus.org/fonts/verdana/Verdana.woffVerdana.woff https://cdn.copernicus.org/fonts/verdana/Verdana.woff — 88.4 KiB — 16 ms — font-display: swaphttps://cdn.copernicus.org/fonts/verdana/Verdana-Bold.woffVerdana-Bold.woff https://cdn.copernicus.org/fonts/verdana/Verdana-Bold.woff — 76.2 KiB — 16 ms — font-display: swap
fontawesome-webfont.ttf unknown swap
Size 97 KB
Load time 60 ms
Start 317 ms
Risk FOUT — text flashes from fallback to web font
Verdana.woff woff swap
Size 88 KB
Load time 16 ms
Start 317 ms
Risk FOUT — text flashes from fallback to web font
  • Convert to woff2 for ~30% smaller file size
Verdana-Bold.woff woff swap
Size 76 KB
Load time 16 ms
Start 318 ms
Risk FOUT — text flashes from fallback to web font
  • Convert to woff2 for ~30% smaller file size
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 ~79 KB and ~158 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
2 hints, 0 missing preconnects
PASS
2 hints, 0 missing preconnects
Info::
Page uses 2 resource hint(s)

Current Resource Hints

preconnect
2
preload
—
dns-prefetch
—
prefetch
—

2 resource hints configured

A
Page Weight Inventory
49 resources · 857 KB · 20 KB savings available
PASS
49 resources · 857 KB · 20 KB savings available
Info::
Within 1MB page-weight target
Got: 857 KB
Warning::
48 third-party resources (99% of weight)
49 resources · 856.8 KiB · 48 third-party Within 1MB page-weight target
Image 49% · 421.6 KiB
Font 31% · 261.9 KiB
CSS 11% · 93.2 KiB
JavaScript 9% · 73.3 KiB
Document 1% · 6.9 KiB

~20.2 KiB of savings available

Remove unused JavaScript: 20.2 KiB
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
49 requests over 794ms
INFO
0 ms 1.0 s 2.0 s 3.0 s 4.0 s 5.0 s 6.0 s FCP 4.6 s LCP 6.6 shttps://copernicus.org// https://copernicus.org/ — 200 — 6.9 KiB — 106 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 — 33.3 KiB — 134 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 — 130 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 — 106 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 — 106 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 — 106 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 — 98 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 — 132 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 — 132 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 — 106 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 — 104 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 — 107 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 — 31.4 KiB — 127 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 — 127 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 — 127 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 — 121 ms — http/1.1https://www.copernicus.org/onload_javascript_actions.jswww.copernicus.org/onload_javascrip... https://www.copernicus.org/onload_javascript_actions.js — 200 — 569 B — 121 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 — 120 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 — 120 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 — 165 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 — 517 B — 164 ms — http/1.1https://www.copernicus.org/template_counter.jswww.copernicus.org/template_counter... https://www.copernicus.org/template_counter.js — 200 — 713 B — 161 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 — 102 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 — 69 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 — 71 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 — 66 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 — 44 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 — 42 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 — 97.4 KiB — 60 ms — http/1.1https://cdn.copernicus.org/fonts/verdana/Verdana.woffcdn.copernicus.org/fonts/verdana/Ve... https://cdn.copernicus.org/fonts/verdana/Verdana.woff — 200 — 88.4 KiB — 16 ms — http/1.1
0 ms 1.0 s 2.0 s 3.0 s 4.0 s 5.0 s 6.0 s FCP 4.6 s LCP 6.6 shttps://copernicus.org// https://copernicus.org/ — 200 — 6.9 KiB — 106 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 — 33.3 KiB — 134 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 — 130 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 — 106 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 — 106 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 — 106 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 — 98 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 — 132 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 — 132 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 — 106 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 — 104 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 — 107 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 — 31.4 KiB — 127 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 — 127 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 — 127 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 — 121 ms — http/1.1https://www.copernicus.org/onload_javascript_actions.jswww.copernicus.org/onload_javascrip... https://www.copernicus.org/onload_javascript_actions.js — 200 — 569 B — 121 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 — 120 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 — 120 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 — 165 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 — 517 B — 164 ms — http/1.1https://www.copernicus.org/template_counter.jswww.copernicus.org/template_counter... https://www.copernicus.org/template_counter.js — 200 — 713 B — 161 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 — 102 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 — 69 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 — 71 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 — 66 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 — 44 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 — 42 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 — 97.4 KiB — 60 ms — http/1.1https://cdn.copernicus.org/fonts/verdana/Verdana.woffcdn.copernicus.org/fonts/verdana/Ve... https://cdn.copernicus.org/fonts/verdana/Verdana.woff — 200 — 88.4 KiB — 16 ms — 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HTML JavaScript CSS Images Fonts XHR/Fetch Other
Third-Party Script Cost
Per-script blocking time, transfer cost, and cache headers
INFO
85% of JavaScript execution is third-party
First-party Third-party 490ms · 33KB · €5/mo
Unattributable
Other
Costly
Execution 298ms
Transfer 0 KB
Monthly Cost €3/mo
cdn.copernicus.org
Other
Optional
Execution 192ms
Transfer 33 KB
Unused 62%
Monthly Cost €2/mo

These scripts may cost more than they're worth

  • Unattributable adds 298ms and costs ~€3/month

85% 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 298ms 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

62% of cdn.copernicus.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

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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