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https://openstreetmap.org

Performance

· 17 checks — Lighthouse + waterfall + sustainability rolled into one auditable list.
SCORE
82
GRADE
B
FIX
3
REVIEW
3
PASS
9
INFO
2

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

Mobile Desktop
64
Performance Overall performance score (0–100) based on Core Web Vitals and other metrics. 90+ is good.
96
Accessibility Measures how accessible the page is for users with disabilities. Checks color contrast, ARIA labels, and semantic HTML.
96
Best Practices Checks for modern web development best practices including HTTPS, no console errors, and secure JavaScript.
92
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.

5.56 s

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

6.16 s

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

20 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.

5.56 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.

6.62 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
9 PASS 3 REVIEW 3 FIX
D
Third-Party Impact
Action
100% third-party, 0 ms blocking
FIX
100% third-party, 0 ms blocking
Warning::
Third-party code accounts for 100% of page weight (894.8 KiB of 895.0 KiB)
Info::
Third-party blocking time is low (0 ms)
100%
First-party Third-party
F
JS Bundles
Action
7 scripts, 384 KB unused
FIX
7 scripts, 384 KB unused
Warning::
https://www.openstreetmap.org/assets/application-c...: 321 KB unused (66%)
Consider code splitting or tree shaking to reduce unused code.
Warning::
https://www.openstreetmap.org/assets/application-c...: unminified — 115 KB could be saved
Warning::
https://www.openstreetmap.org/assets/index-e3ac32a...: 33 KB unused (76%)
Consider code splitting or tree shaking to reduce unused code.
Warning::
https://www.openstreetmap.org/assets/index-e3ac32a...: unminified — 14 KB could be saved
Warning::
https://www.openstreetmap.org/assets/turbo-ddc4446...: 30 KB unused (84%)
Consider code splitting or tree shaking to reduce unused code.
Info::
Total unused JavaScript: 384 KB
384 KB unused JavaScript

Downloaded but never executed on this page.

ScriptSizeUnusedMinifiedParty
https://www.openstreetmap.org/assets/application-c54179f4131c35c0bda3948cb81c345c2da4a81d7ed270b94c70dc2ae7a1dda8.js490 KB321 KB (66%)✗3rd
https://www.openstreetmap.org/assets/index-e3ac32a59914bec0aac759b752393239d44d5f9baf1cc067af403f1f03b77e14.js44 KB33 KB (76%)✗3rd
https://www.openstreetmap.org/assets/turbo-ddc44468c3f2a177272c2635e622ef6a909e2fa74c250a9f98a31a94a87d1d29.js35 KB30 KB (84%)✗3rd
https://www.openstreetmap.org/assets/i18n/en-dd1b503e1e8daf7760ea43a9cfa0866825e87e455d6f6a0d661aad6536be460d.js11 KB—✗3rd
blob:https://www.openstreetmap.org/9342c12f-90dc-4e16-b397-c1f50c1a06e5-0 KB—✓3rd
https://www.openstreetmap.org/assets/make-plural/cardinals-cbbf892e6bf25f4dbbcf7776eee157ce78502c06a15a02ad32ca39aecfc50867.js2 KB—✓3rd
https://matomo.openstreetmap.org/matomo.js19 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

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

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

F
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.

No Cache-Control header

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

B
Image Optimization
10 images, 0 KB saveable
REVIEW
10 images, 0 KB saveable
Info::
All images are well-optimized
10 images 63 KB
0 oversized -0 KB
10 legacy format
0 missing dimensions CLS risk
C
JS Execution Cost
Action
1443ms total JS execution
REVIEW
1443ms total JS execution
Warning::
https://www.openstreetmap.org/assets/application-c...: 856ms CPU time
Warning::
Unattributable: 393ms CPU time
Info::
https://www.openstreetmap.org/: 194ms CPU time
Warning::
Third-party scripts: 1443ms (100% of total)

Main Thread Breakdown

Script Evaluation 36% Other 27% Script Parsing & Compilation 21% Style & Layout 10% Parse HTML & CSS 3%
ScriptTotalScriptingParse/CompileParty
https://www.openstreetmap.org/assets/application-c54179f4131c35c0bda3948cb81c345c2da4a81d7ed270b94c70dc2ae7a1dda8.js856ms484ms286ms3rd
Unattributable393ms17ms0ms3rd
https://www.openstreetmap.org/194ms6ms1ms3rd
B
Page Weight Inventory
30 resources · 895 KB · 384 KB savings available
REVIEW
30 resources · 895 KB · 384 KB savings available
Info::
Within 1MB page-weight target
Got: 895 KB
Info::
~384 KB of savings available
Warning::
29 third-party resources (100% of weight)
Info::
1 resources over 200KB
30 resources · 895.0 KiB · 29 third-party Within 1MB page-weight target
JavaScript 67% · 601.4 KiB
Font 15% · 131.2 KiB
Image 11% · 94.1 KiB
CSS 6% · 56.6 KiB
Document 1% · 10.5 KiB
Other 0% · 1.2 KiB

~383.7 KiB of savings available

Remove unused JavaScript: 383.7 KiB
A
Page Weight Budget
895 KB transferred, 30 requests
PASS
895 KB transferred, 30 requests
Info::
Page weighs 3.7 MB (895 KB transferred)
Warning::
JavaScript is 601 KB — consider code splitting or lazy loading
Large JavaScript bundles delay interactivity. Split code by route or defer non-critical scripts.
Got: 601 KB
Info::
30 HTTP requests
Info::
Estimated 0.18 g CO2 per page load
895 KB / 2.4 MB budget
895 KB transferred
30 requests
0.18 g CO2 per page load
JavaScript 601.4 KiB 67%
Fonts 131.2 KiB 15%
Images 62.8 KiB 7%
CSS 56.6 KiB 6%
Other 31.5 KiB 4%
HTML 8.5 KiB 1%
Other 2.0 KiB 0%
Other 961 B 0%
Other 102 B 0%
0 2.4 MB 4.9 MB
Under budget

Large JavaScript bundles delay interactivity. Split code by route or defer non-critical scripts.

Why this matters

JavaScript bundle is large — code-split routes and lazy-load off-screen components to defer.

Source: web.dev

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
1 fonts (131 KB)
PASS
1 fonts (131 KB)
Info::
1 font(s) use font-display: swap (FOUT risk but functional)

Web fonts

1

131 KB total

Render-blocking

0

of 1

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 5.6 s LCP 6.2 shttps://www.openstreetmap.org/assets/bootstrap-icons/font/fonts/bootstrap-icons-d58dbdc0232480708b000373bb9f5be99101ea5a95df6a9ef080912f10588790.woff2?24e3eb84d0bcaf83d77f904c78ac1f47bootstrap-icons-d58dbdc... https://www.openstreetmap.org/assets/bootstrap-icons/font/fonts/bootstrap-icons-d58dbdc0232480708b000373bb9f5be99101ea5a95df6a9ef080912f10588790.woff2?24e3eb84d0bcaf83d77f904c78ac1f47 — 131.2 KiB — 9 ms — font-display: swap
bootstrap-icons-d58dbdc... woff2 swap
Size 131 KB
Load time 9 ms
Start 688 ms
Risk FOUT — 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
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 ~66 KB and ~132 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
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
A+
Green Hosting
Whether the site is served from green-energy infrastructure
PASS

Green Hosting

This site is hosted on green energy infrastructure

Provider: Cloudflare

Network Waterfall
30 requests over 1999ms
INFO
0 ms 1.0 s 2.0 s 3.0 s 4.0 s 5.0 s 6.0 s FCP 5.6 s LCP 6.2 shttps://openstreetmap.org// https://openstreetmap.org/ — 301 — 176 B — 20 ms — h2https://www.openstreetmap.org/www.openstreetmap.org/ https://www.openstreetmap.org/ — 200 — 8.5 KiB — 327 ms — h2https://www.openstreetmap.org/assets/index-e3ac32a59914bec0aac759b752393239d44d5f9baf1cc067af403f1f03b77e14.jswww.openstreetmap.org/assets/index-... https://www.openstreetmap.org/assets/index-e3ac32a59914bec0aac759b752393239d44d5f9baf1cc067af403f1f03b77e14.js — 200 — 44.2 KiB — 8 ms — h2https://www.openstreetmap.org/assets/turbo-ddc44468c3f2a177272c2635e622ef6a909e2fa74c250a9f98a31a94a87d1d29.jswww.openstreetmap.org/assets/turbo-... https://www.openstreetmap.org/assets/turbo-ddc44468c3f2a177272c2635e622ef6a909e2fa74c250a9f98a31a94a87d1d29.js — 200 — 35.4 KiB — 33 ms — h3https://www.openstreetmap.org/assets/application-c54179f4131c35c0bda3948cb81c345c2da4a81d7ed270b94c70dc2ae7a1dda8.jswww.openstreetmap.org/assets/applic... https://www.openstreetmap.org/assets/application-c54179f4131c35c0bda3948cb81c345c2da4a81d7ed270b94c70dc2ae7a1dda8.js — 200 — 489.9 KiB — 57 ms — h3https://www.openstreetmap.org/assets/i18n/en-dd1b503e1e8daf7760ea43a9cfa0866825e87e455d6f6a0d661aad6536be460d.jswww.openstreetmap.org/assets/i18n/e... https://www.openstreetmap.org/assets/i18n/en-dd1b503e1e8daf7760ea43a9cfa0866825e87e455d6f6a0d661aad6536be460d.js — 200 — 10.5 KiB — 29 ms — h3https://www.openstreetmap.org/assets/screen-auto-ltr-46573c72fca1195477837776bb421b53339db3f9a4345c51a3589b4a29185ce4.csswww.openstreetmap.org/assets/screen... https://www.openstreetmap.org/assets/screen-auto-ltr-46573c72fca1195477837776bb421b53339db3f9a4345c51a3589b4a29185ce4.css — 200 — 43.4 KiB — 28 ms — h3https://www.openstreetmap.org/assets/print-ltr-97dee1ca487394c852f28c2906a930316ab6d2cacf7f73e47c1c31fad8919051.csswww.openstreetmap.org/assets/print-... https://www.openstreetmap.org/assets/print-ltr-97dee1ca487394c852f28c2906a930316ab6d2cacf7f73e47c1c31fad8919051.css — 200 — 747 B — 17 ms — h3https://www.openstreetmap.org/assets/leaflet-all-d3e8505f47e0f0615d3daf2619f2267c086cbe9e17e276f393ee686dca54e0d3.csswww.openstreetmap.org/assets/leafle... https://www.openstreetmap.org/assets/leaflet-all-d3e8505f47e0f0615d3daf2619f2267c086cbe9e17e276f393ee686dca54e0d3.css — 200 — 3.1 KiB — 18 ms — h3https://www.openstreetmap.org/assets/maplibre-gl-all-671191c247be2831d2737d30b396112dc1041453bd6291863062bbaea52a940a.csswww.openstreetmap.org/assets/maplib... https://www.openstreetmap.org/assets/maplibre-gl-all-671191c247be2831d2737d30b396112dc1041453bd6291863062bbaea52a940a.css — 200 — 9.4 KiB — 19 ms — h3https://www.openstreetmap.org/assets/manifest-97cb57bafa7f7f002cc5fe5532b856c4246eef5cbbd21c78b4c6bc2ffa46747a.jsonwww.openstreetmap.org/assets/manife... https://www.openstreetmap.org/assets/manifest-97cb57bafa7f7f002cc5fe5532b856c4246eef5cbbd21c78b4c6bc2ffa46747a.json — 200 — 961 B — 25 ms — h3https://www.openstreetmap.org/assets/osm_logo-cc7d94392992162133be3baa21a37eb84f19f9b91178f704005378fbeecabb4e.svgwww.openstreetmap.org/assets/osm_lo... https://www.openstreetmap.org/assets/osm_logo-cc7d94392992162133be3baa21a37eb84f19f9b91178f704005378fbeecabb4e.svg — 200 — 10.0 KiB — 7 ms — h3blob:https://www.openstreetmap.org/9342c12f-90dc-4e16-b397-c1f50c1a06e5www.openstreetmap.org/9342c12f-90dc... blob:https://www.openstreetmap.org/9342c12f-90dc-4e16-b397-c1f50c1a06e5 — 200 — -1 B — 76 ms — blobhttps://www.openstreetmap.org/assets/make-plural/cardinals-cbbf892e6bf25f4dbbcf7776eee157ce78502c06a15a02ad32ca39aecfc50867.jswww.openstreetmap.org/assets/make-p... https://www.openstreetmap.org/assets/make-plural/cardinals-cbbf892e6bf25f4dbbcf7776eee157ce78502c06a15a02ad32ca39aecfc50867.js — 200 — 2.3 KiB — 5 ms — h3https://www.openstreetmap.org/assets/leaflet/dist/images/marker-shadow-a2d94406ba198f61f68a71ed8f9f9c701122c0c33b775d990edceae4aece567f.pngwww.openstreetmap.org/assets/leafle... https://www.openstreetmap.org/assets/leaflet/dist/images/marker-shadow-a2d94406ba198f61f68a71ed8f9f9c701122c0c33b775d990edceae4aece567f.png — 200 — 932 B — 6 ms — h3https://www.openstreetmap.org/assets/bootstrap-icons/font/fonts/bootstrap-icons-d58dbdc0232480708b000373bb9f5be99101ea5a95df6a9ef080912f10588790.woff2?24e3eb84d0bcaf83d77f904c78ac1f47www.openstreetmap.org/assets/bootst... https://www.openstreetmap.org/assets/bootstrap-icons/font/fonts/bootstrap-icons-d58dbdc0232480708b000373bb9f5be99101ea5a95df6a9ef080912f10588790.woff2?24e3eb84d0bcaf83d77f904c78ac1f47 — 200 — 131.2 KiB — 9 ms — h3https://matomo.openstreetmap.org/matomo.jsmatomo.openstreetmap.org/matomo.js https://matomo.openstreetmap.org/matomo.js — 200 — 19.2 KiB — 339 ms — h2https://www.openstreetmap.org/panes/layerswww.openstreetmap.org/panes/layers https://www.openstreetmap.org/panes/layers — 200 — 2.0 KiB — 309 ms — h3https://tile.openstreetmap.org/3/1/2.pngtile.openstreetmap.org/3/1/2.png https://tile.openstreetmap.org/3/1/2.png — 200 — 9.4 KiB — 29 ms — h2https://tile.openstreetmap.org/3/2/2.pngtile.openstreetmap.org/3/2/2.png https://tile.openstreetmap.org/3/2/2.png — 200 — 8.9 KiB — 28 ms — h2https://tile.openstreetmap.org/3/1/3.pngtile.openstreetmap.org/3/1/3.png https://tile.openstreetmap.org/3/1/3.png — 200 — 3.3 KiB — 28 ms — h2https://tile.openstreetmap.org/3/2/3.pngtile.openstreetmap.org/3/2/3.png https://tile.openstreetmap.org/3/2/3.png — 200 — 4.9 KiB — 27 ms — h2https://tile.openstreetmap.org/3/1/1.pngtile.openstreetmap.org/3/1/1.png https://tile.openstreetmap.org/3/1/1.png — 200 — 10.1 KiB — 29 ms — h2https://tile.openstreetmap.org/3/2/1.pngtile.openstreetmap.org/3/2/1.png https://tile.openstreetmap.org/3/2/1.png — 200 — 8.5 KiB — 30 ms — h2https://tile.openstreetmap.org/3/1/4.pngtile.openstreetmap.org/3/1/4.png https://tile.openstreetmap.org/3/1/4.png — 200 — 430 B — 16 ms — h2https://tile.openstreetmap.org/3/2/4.pngtile.openstreetmap.org/3/2/4.png https://tile.openstreetmap.org/3/2/4.png — 200 — 6.3 KiB — 20 ms — h2https://matomo.openstreetmap.org/matomo.php?action_name=OpenStreetMap&idsite=1&rec=1&r=290177&h=18&m=16&s=8&url=https%3A%2F%2Fwww.openstreetmap.org%2F%23map%3D3%2F38.01%2F-95.84&_id=376c5fd996917c6d&_idn=1&send_image=0&_refts=0&pv_id=MAQ0A2&webgl=1&pf_net=0&pf_srv=318&pf_tfr=2&pf_dm1=324&uadata=%7B%22formFactors%22%3A%5B%22Desktop%22%5D%2C%22fullVersionList%22%3A%5B%7B%22brand%22%3A%22Not-A.Brand%22%2C%22version%22%3A%2224.0.0.0%22%7D%2C%7B%22brand%22%3A%22Chromium%22%2C%22version%22%3A%22146.0.7680.164%22%7D%5D%2C%22mobile%22%3Atrue%2C%22model%22%3A%22moto%20g%20power%20(2022)%22%2C%22platform%22%3A%22Android%22%2C%22platformVersion%22%3A%2211.0%22%7D&pdf=1&qt=0&realp=0&wma=0&fla=0&java=0&ag=0&cookie=1&res=412x823matomo.openstreetmap.org/matomo.php... https://matomo.openstreetmap.org/matomo.php?action_name=OpenStreetMap&idsite=1&rec=1&r=290177&h=18&m=16&s=8&url=https%3A%2F%2Fwww.openstreetmap.org%2F%23map%3D3%2F38.01%2F-95.84&_id=376c5fd996917c6d&_idn=1&send_image=0&_refts=0&pv_id=MAQ0A2&webgl=1&pf_net=0&pf_srv=318&pf_tfr=2&pf_dm1=324&uadata=%7B%22formFactors%22%3A%5B%22Desktop%22%5D%2C%22fullVersionList%22%3A%5B%7B%22brand%22%3A%22Not-A.Brand%22%2C%22version%22%3A%2224.0.0.0%22%7D%2C%7B%22brand%22%3A%22Chromium%22%2C%22version%22%3A%22146.0.7680.164%22%7D%5D%2C%22mobile%22%3Atrue%2C%22model%22%3A%22moto%20g%20power%20(2022)%22%2C%22platform%22%3A%22Android%22%2C%22platformVersion%22%3A%2211.0%22%7D&pdf=1&qt=0&realp=0&wma=0&fla=0&java=0&ag=0&cookie=1&res=412x823 — 204 — 87 B — 140 ms — h2https://www.openstreetmap.org/assets/favicon-32x32-99b88fcadeef736889823c8a886b89d8cada9d4423a49a27de29bacc0a6bebd1.pngwww.openstreetmap.org/assets/favico... https://www.openstreetmap.org/assets/favicon-32x32-99b88fcadeef736889823c8a886b89d8cada9d4423a49a27de29bacc0a6bebd1.png — 200 — 2.9 KiB — 10 ms — h3https://www.openstreetmap.org/assets/android-chrome-144x144-1ca102662af5366ff980871b959678d7ff7377cd9093cb0431dabb6c6010b723.pngwww.openstreetmap.org/assets/androi... https://www.openstreetmap.org/assets/android-chrome-144x144-1ca102662af5366ff980871b959678d7ff7377cd9093cb0431dabb6c6010b723.png — 200 — 28.4 KiB — 28 ms — h3https://matomo.openstreetmap.org/matomo.php?idgoal=3&idsite=1&rec=1&r=963428&h=18&m=16&s=8&url=https%3A%2F%2Fwww.openstreetmap.org%2F%23map%3D3%2F38.01%2F-95.84&_id=376c5fd996917c6d&_idn=0&send_image=0&_refts=0&pv_id=MAQ0A2&uadata=%7B%22formFactors%22%3A%5B%22Desktop%22%5D%2C%22fullVersionList%22%3A%5B%7B%22brand%22%3A%22Not-A.Brand%22%2C%22version%22%3A%2224.0.0.0%22%7D%2C%7B%22brand%22%3A%22Chromium%22%2C%22version%22%3A%22146.0.7680.164%22%7D%5D%2C%22mobile%22%3Atrue%2C%22model%22%3A%22moto%20g%20power%20(2022)%22%2C%22platform%22%3A%22Android%22%2C%22platformVersion%22%3A%2211.0%22%7D&pdf=1&qt=0&realp=0&wma=0&fla=0&java=0&ag=0&cookie=1&res=412x823matomo.openstreetmap.org/matomo.php... https://matomo.openstreetmap.org/matomo.php?idgoal=3&idsite=1&rec=1&r=963428&h=18&m=16&s=8&url=https%3A%2F%2Fwww.openstreetmap.org%2F%23map%3D3%2F38.01%2F-95.84&_id=376c5fd996917c6d&_idn=0&send_image=0&_refts=0&pv_id=MAQ0A2&uadata=%7B%22formFactors%22%3A%5B%22Desktop%22%5D%2C%22fullVersionList%22%3A%5B%7B%22brand%22%3A%22Not-A.Brand%22%2C%22version%22%3A%2224.0.0.0%22%7D%2C%7B%22brand%22%3A%22Chromium%22%2C%22version%22%3A%22146.0.7680.164%22%7D%5D%2C%22mobile%22%3Atrue%2C%22model%22%3A%22moto%20g%20power%20(2022)%22%2C%22platform%22%3A%22Android%22%2C%22platformVersion%22%3A%2211.0%22%7D&pdf=1&qt=0&realp=0&wma=0&fla=0&java=0&ag=0&cookie=1&res=412x823 — 204 — 15 B — 123 ms — h2
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-party 1443ms · 498KB · $19/mo
www.openstreetmap.org
Other
Costly
Execution 856ms
Transfer 490 KB
Unused 66%
Monthly Cost $11/mo
Unattributable
Other
Costly
Execution 393ms
Transfer 0 KB
Monthly Cost $5/mo
www.openstreetmap.org
Other
Optional
Execution 194ms
Transfer 8 KB
Monthly Cost $3/mo

These scripts may cost more than they're worth

  • www.openstreetmap.org adds 856ms and costs ~$11/month
  • Unattributable adds 393ms and costs ~$5/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.

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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.openstreetmap.org takes 856ms 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

66% of www.openstreetmap.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

Unattributable takes 393ms 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

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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