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Performance

· 17 checks — Lighthouse + waterfall + sustainability rolled into one auditable list.
SCORE
90
GRADE
A
FIX
2
REVIEW
3
PASS
10
INFO
2

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

Mobile Desktop
78
Performance Overall performance score (0–100) based on Core Web Vitals and other metrics. 90+ is good.
90
Accessibility Measures how accessible the page is for users with disabilities. Checks color contrast, ARIA labels, and semantic HTML.
100
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.

2.16 s

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

4.14 s

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

212 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.

4.27 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.

4.14 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
64% third-party, 0 ms blocking
FIX
64% third-party, 0 ms blocking
Warning::
Third-party code accounts for 64% of page weight (169.8 KiB of 263.6 KiB)
Info::
Third-party blocking time is low (0 ms)
36%
64%
First-party Third-party
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
JS Execution Cost
722ms total JS execution
REVIEW
722ms total JS execution
Warning::
https://www.googletagmanager.com/gtag/js?id=G-ZLCV...: 276ms CPU time
Info::
Unattributable: 197ms CPU time
Info::
https://nmap.org/: 180ms CPU time
Info::
https://www.google-analytics.com/analytics.js: 69ms CPU time
Warning::
Third-party scripts: 542ms (75% of total)

Main Thread Breakdown

Script Evaluation 48% Other 23% Style & Layout 16% Script Parsing & Compilation 8% Rendering 3%
ScriptTotalScriptingParse/CompileParty
https://www.googletagmanager.com/gtag/js?id=G-ZLCVHN7NXS&cx=c&_slc=1276ms220ms52ms3rd
Unattributable197ms67ms0ms3rd
https://nmap.org/180ms8ms2ms1st
https://www.google-analytics.com/analytics.js69ms57ms6ms3rd
B
JS Bundles
3 scripts, 63 KB unused
REVIEW
3 scripts, 63 KB unused
Warning::
https://www.googletagmanager.com/gtag/js?id=G-ZLCV...: 63 KB unused (43%)
Consider code splitting or tree shaking to reduce unused code.
Info::
Total unused JavaScript: 63 KB
63 KB unused JavaScript

Downloaded but never executed on this page.

ScriptSizeUnusedMinifiedParty
https://www.googletagmanager.com/gtag/js?id=G-ZLCVHN7NXS&cx=c&_slc=1148 KB63 KB (43%)✓3rd
https://www.google-analytics.com/analytics.js21 KB—✓3rd
https://nmap.org/shared/js/nst.js?v=23 KB—✓1st

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

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

Green Hosting

No green hosting detected

A+
Page Weight Budget
264 KB transferred, 13 requests
PASS
264 KB transferred, 13 requests
Info::
Page weighs 563 KB (264 KB transferred)
Info::
13 HTTP requests
Info::
Estimated 0.05 g CO2 per page load
264 KB / 2.4 MB budget
264 KB transferred
13 requests
0.05 g CO2 per page load
JavaScript 171.8 KiB 65%
Images 63.8 KiB 24%
HTML 19.6 KiB 7%
CSS 7.1 KiB 3%
Other 919 B 0%
Other 460 B 0%
Other 20 B 0%
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
Image Optimization
3 images, 0 KB saveable
PASS
3 images, 0 KB saveable
Info::
All images are well-optimized
3 images 64 KB
0 oversized -0 KB
3 legacy format
0 missing dimensions CLS risk
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
3 hints, 0 missing preconnects
PASS
3 hints, 0 missing preconnects
Info::
Page uses 3 resource hint(s)

Current Resource Hints

preconnect
—
preload
3
dns-prefetch
—
prefetch
—

3 resource hints configured

A
Page Weight Inventory
13 resources · 264 KB · 63 KB savings available
PASS
13 resources · 264 KB · 63 KB savings available
Info::
Within 1MB page-weight target
Got: 264 KB
Info::
~63 KB of savings available
Warning::
5 third-party resources (64% of weight)
13 resources · 263.6 KiB · 5 third-party Within 1MB page-weight target
JavaScript 65% · 171.8 KiB
Image 25% · 64.7 KiB
Document 7% · 19.6 KiB
CSS 3% · 7.1 KiB
Other 0% · 480 B

~63.3 KiB of savings available

Remove unused JavaScript: 63.3 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
13 requests over 741ms
INFO
0 ms 1.0 s 2.0 s 3.0 s 4.0 s FCP 2.2 s LCP 4.1 shttps://nmap.org// https://nmap.org/ — 200 — 19.6 KiB — 319 ms — http/1.1https://nmap.org/images/sitelogo-2x.png/images/sitelogo-2x.png https://nmap.org/images/sitelogo-2x.png — 200 — 58.7 KiB — 195 ms — http/1.1https://nmap.org/shared/images/nst-icons.svg/shared/images/nst-icons.svg https://nmap.org/shared/images/nst-icons.svg — 200 — 5.1 KiB — 195 ms — http/1.1https://nmap.org/shared/css/nst.css?v=2/shared/css/nst.css?v=2 https://nmap.org/shared/css/nst.css?v=2 — 200 — 4.9 KiB — 111 ms — http/1.1https://nmap.org/site.css/site.css https://nmap.org/site.css — 200 — 1.2 KiB — 174 ms — http/1.1https://www.google-analytics.com/analytics.jswww.google-analytics.com/analytics.... https://www.google-analytics.com/analytics.js — 200 — 20.9 KiB — 17 ms — h2https://www.google-analytics.com/j/collect?v=1&_v=j102&a=1633833410&t=pageview&_s=1&dl=https%3A%2F%2Fnmap.org%2F&ul=en-us&dt=Nmap%3A%20the%20Network%20Mapper%20-%20Free%20Security%20Scanner&sr=412x823&vp=412x823&_u=IEBAAEABAAAAACAAI~&jid=1972037667&gjid=1906301370&cid=421283477.1776897099&tid=UA-11009417-1&_gid=475847425.1776897099&_r=1&_slc=1&z=1053667048www.google-analytics.com/j/collect?... https://www.google-analytics.com/j/collect?v=1&_v=j102&a=1633833410&t=pageview&_s=1&dl=https%3A%2F%2Fnmap.org%2F&ul=en-us&dt=Nmap%3A%20the%20Network%20Mapper%20-%20Free%20Security%20Scanner&sr=412x823&vp=412x823&_u=IEBAAEABAAAAACAAI~&jid=1972037667&gjid=1906301370&cid=421283477.1776897099&tid=UA-11009417-1&_gid=475847425.1776897099&_r=1&_slc=1&z=1053667048 — 200 — 460 B — 21 ms — h2https://nmap.org/shared/js/nst.js?v=2/shared/js/nst.js?v=2 https://nmap.org/shared/js/nst.js?v=2 — 200 — 2.6 KiB — 66 ms — http/1.1https://nmap.org/shared/css/nst-foot.css?v=2/shared/css/nst-foot.css?v=2 https://nmap.org/shared/css/nst-foot.css?v=2 — 200 — 969 B — 67 ms — http/1.1https://www.googletagmanager.com/gtag/js?id=G-ZLCVHN7NXS&cx=c&_slc=1www.googletagmanager.com/gtag/js?id... https://www.googletagmanager.com/gtag/js?id=G-ZLCVHN7NXS&cx=c&_slc=1 — 200 — 148.3 KiB — 70 ms — h2https://www.google-analytics.com/g/collect?v=2&tid=G-ZLCVHN7NXS&gtm=45je64k0v9134945724za20g&_p=1776897099270&gcd=13l3l3l3l2l1&npa=0&dma=0&_eu=ABAI&are=1&cid=421283477.1776897099&frm=0&pscdl=noapi&rcb=12&sr=412x823&uaa=&uab=64&uafvl=Not-A.Brand%3B24.0.0.0%7CChromium%3B146.0.7680.164&uam=moto%20g%20power%20(2022)&uamb=1&uap=Android&uapv=11.0&uaw=0&ul=en-us&_s=1&tag_exp=0~115616986~115938466~115938469~117266401~117512543~117884344&dl=https%3A%2F%2Fnmap.org%2F&dt=Nmap%3A%20the%20Network%20Mapper%20-%20Free%20Security%20Scanner&sid=1776897099&sct=1&seg=0&_tu=wAQ&en=page_view&_fv=1&_ss=1&_ee=1&tfd=662www.google-analytics.com/g/collect?... https://www.google-analytics.com/g/collect?v=2&tid=G-ZLCVHN7NXS&gtm=45je64k0v9134945724za20g&_p=1776897099270&gcd=13l3l3l3l2l1&npa=0&dma=0&_eu=ABAI&are=1&cid=421283477.1776897099&frm=0&pscdl=noapi&rcb=12&sr=412x823&uaa=&uab=64&uafvl=Not-A.Brand%3B24.0.0.0%7CChromium%3B146.0.7680.164&uam=moto%20g%20power%20(2022)&uamb=1&uap=Android&uapv=11.0&uaw=0&ul=en-us&_s=1&tag_exp=0~115616986~115938466~115938469~117266401~117512543~117884344&dl=https%3A%2F%2Fnmap.org%2F&dt=Nmap%3A%20the%20Network%20Mapper%20-%20Free%20Security%20Scanner&sid=1776897099&sct=1&seg=0&_tu=wAQ&en=page_view&_fv=1&_ss=1&_ee=1&tfd=662 — 204 — 20 B — 21 ms — h3https://www.googletagmanager.com/a?v=3&t=l&pid=1755709533&rv=64k0&tag_exp=0~115616986~115938466~115938469~117266401~117512543~117884344&u=AAAAAAAIAAAAACCAAAE&h=Ag&gtm=45je64k0v9134945724za20g&cl=3.1.0&ccid=134945724&cid=G-ZLCVHN7NXS&l=L499.S40.B0.E25.I468.TC12.HTC0.C0~gtm.init_consent.S4.V2.E50.TS5ogtdma.TI13.TE1~gtm.init.S0.V0.E44.TS5ogtgasend.TI10.TE1.TS5ogtsessiontimeout.TI12.TE1.TS5ogt1pdatav2.TI15.TE1.TS5ccdgafirst.TI22.TE0.TS5setproductsettings.TI21.TE0.TS5ogtgagamlink.TI20.TE1.TS5ccdgaregscope.TI19.TE1.TS5ccdconversionmarking.TI18.TE0.TS5ccdautoredact.TI17.TE0.TS5ccdgalast.TI16.TE0~gtm.js.S0.V0.E32.TS5gct.TI7.TE2~gtm.dom.S0.V0.E8~gtm.load.S0.V0.E0~GA163www.googletagmanager.com/a?v=3&t=l&... https://www.googletagmanager.com/a?v=3&t=l&pid=1755709533&rv=64k0&tag_exp=0~115616986~115938466~115938469~117266401~117512543~117884344&u=AAAAAAAIAAAAACCAAAE&h=Ag&gtm=45je64k0v9134945724za20g&cl=3.1.0&ccid=134945724&cid=G-ZLCVHN7NXS&l=L499.S40.B0.E25.I468.TC12.HTC0.C0~gtm.init_consent.S4.V2.E50.TS5ogtdma.TI13.TE1~gtm.init.S0.V0.E44.TS5ogtgasend.TI10.TE1.TS5ogtsessiontimeout.TI12.TE1.TS5ogt1pdatav2.TI15.TE1.TS5ccdgafirst.TI22.TE0.TS5setproductsettings.TI21.TE0.TS5ogtgagamlink.TI20.TE1.TS5ccdgaregscope.TI19.TE1.TS5ccdconversionmarking.TI18.TE0.TS5ccdautoredact.TI17.TE0.TS5ccdgalast.TI16.TE0~gtm.js.S0.V0.E32.TS5gct.TI7.TE2~gtm.dom.S0.V0.E8~gtm.load.S0.V0.E0~GA163 — 200 — 59 B — 27 ms — h2https://nmap.org/shared/images/tiny-eyeicon.png/shared/images/tiny-eyeicon.png https://nmap.org/shared/images/tiny-eyeicon.png — 200 — 919 B — 65 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
75% of JavaScript execution is third-party
First-party Third-party 542ms · 169KB · €6/mo
Google Tag Manager
Tag Manager
Costly
Execution 276ms
Transfer 148 KB
Unused 43%
Monthly Cost €3/mo
Unattributable
Other
Optional
Execution 197ms
Transfer 0 KB
Monthly Cost €2/mo
Google Analytics
Analytics
Optional
Execution 69ms
Transfer 21 KB
Monthly Cost €1/mo

These scripts may cost more than they're worth

  • Google Tag Manager adds 276ms and costs ~€3/month

75% 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

Google Tag Manager takes 276ms 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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