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https://wireshark.org

Performance

· 17 checks — Lighthouse + waterfall + sustainability rolled into one auditable list.
SCORE
88
GRADE
B
FIX
2
REVIEW
2
PASS
11
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.
84
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.

3.36 s

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

4.28 s

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

101 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.

3.36 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.

5.72 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
11 PASS 2 REVIEW 2 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 (847.3 KiB of 847.9 KiB)
Info::
Third-party blocking time is low (0 ms)
100%
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.

C
JS Execution Cost
Action
1163ms total JS execution
REVIEW
1163ms total JS execution
Warning::
https://www.wireshark.org/: 678ms CPU time
Warning::
https://www.googletagmanager.com/gtag/js?id=G-YLHR...: 311ms CPU time
Info::
Unattributable: 174ms CPU time
Warning::
Third-party scripts: 1163ms (100% of total)

Main Thread Breakdown

Script Evaluation 40% Style & Layout 18% Parse HTML & CSS 17% Other 16% Script Parsing & Compilation 7%
ScriptTotalScriptingParse/CompileParty
https://www.wireshark.org/678ms182ms10ms3rd
https://www.googletagmanager.com/gtag/js?id=G-YLHRKD6LH6311ms244ms65ms3rd
Unattributable174ms29ms0ms3rd
B
JS Bundles
2 scripts, 67 KB unused
REVIEW
2 scripts, 67 KB unused
Warning::
https://www.googletagmanager.com/gtag/js?id=G-YLHR...: 67 KB unused (41%)
Consider code splitting or tree shaking to reduce unused code.
Info::
Total unused JavaScript: 67 KB
67 KB unused JavaScript

Downloaded but never executed on this page.

ScriptSizeUnusedMinifiedParty
https://www.googletagmanager.com/gtag/js?id=G-YLHRKD6LH6164 KB67 KB (41%)✓3rd
https://static.cloudflareinsights.com/beacon.min.js11 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
Page Weight Budget
848 KB transferred, 18 requests
PASS
848 KB transferred, 18 requests
Info::
Page weighs 1.4 MB (848 KB transferred)
Info::
18 HTTP requests
Info::
Estimated 0.17 g CO2 per page load
848 KB / 2.4 MB budget
848 KB transferred
18 requests
0.17 g CO2 per page load
Images 583.7 KiB 69%
JavaScript 174.9 KiB 21%
HTML 43.0 KiB 5%
CSS 25.1 KiB 3%
Fonts 15.6 KiB 2%
Other 5.0 KiB 1%
Other 551 B 0%
Other 35 B 0%
Other 0 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
5 images, 0 KB saveable
PASS
5 images, 0 KB saveable
Info::
All images are well-optimized
5 images 584 KB
0 oversized -0 KB
2 legacy format
0 missing dimensions CLS risk
A+
Font Loading
1 fonts (16 KB)
PASS
1 fonts (16 KB)
Info::
1 font(s) use font-display: swap (FOUT risk but functional)

Web fonts

1

16 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 FCP 3.4 s LCP 4.3 shttps://use.typekit.net/af/5d9976/000000000000000077359bd4/31/l?primer=7cdcb44be4a7db8877ffa5c0007b8dd865b3bbc383831fe2ea177f62257a9191&fvd=n4&v=3l https://use.typekit.net/af/5d9976/000000000000000077359bd4/31/l?primer=7cdcb44be4a7db8877ffa5c0007b8dd865b3bbc383831fe2ea177f62257a9191&fvd=n4&v=3 — 15.6 KiB — 10 ms — font-display: swap
l woff2 swap
Size 16 KB
Load time 10 ms
Start 186 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)
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
18 resources · 848 KB · 67 KB savings available
PASS
18 resources · 848 KB · 67 KB savings available
Info::
Within 1MB page-weight target
Got: 848 KB
Info::
~67 KB of savings available
Warning::
17 third-party resources (100% of weight)
Info::
1 resources over 200KB
18 resources · 847.9 KiB · 17 third-party Within 1MB page-weight target
Image 69% · 588.1 KiB
JavaScript 21% · 174.9 KiB
Document 5% · 43.6 KiB
CSS 3% · 25.1 KiB
Font 2% · 15.6 KiB
Other 0% · 586 B

~66.9 KiB of savings available

Remove unused JavaScript: 66.9 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
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
18 requests over 431ms
INFO
0 ms 1.0 s 2.0 s 3.0 s 4.0 s FCP 3.4 s LCP 4.3 shttps://wireshark.org// https://wireshark.org/ — 301 — 557 B — 32 ms — h3https://www.wireshark.org/www.wireshark.org/ https://www.wireshark.org/ — 200 — 43.0 KiB — 36 ms — h3https://www.googletagmanager.com/gtag/js?id=G-YLHRKD6LH6www.googletagmanager.com/gtag/js?id... https://www.googletagmanager.com/gtag/js?id=G-YLHRKD6LH6 — 200 — 164.2 KiB — 72 ms — h2https://cdn.jsdelivr.net/npm/wf-components/public/styles.csscdn.jsdelivr.net/npm/wf-components/... https://cdn.jsdelivr.net/npm/wf-components/public/styles.css — 200 — 8.1 KiB — 33 ms — h2https://use.typekit.net/nvp0lhj.cssuse.typekit.net/nvp0lhj.css https://use.typekit.net/nvp0lhj.css — 200 — 1.3 KiB — 19 ms — h2https://www.wireshark.org/_astro/bibliography.CChv4xRK.csswww.wireshark.org/_astro/bibliograp... https://www.wireshark.org/_astro/bibliography.CChv4xRK.css — 200 — 15.5 KiB — 16 ms — h3https://static.cloudflareinsights.com/beacon.min.jsstatic.cloudflareinsights.com/beaco... https://static.cloudflareinsights.com/beacon.min.js — 200 — 10.7 KiB — 28 ms — h2https://p.typekit.net/p.css?s=1&k=nvp0lhj&ht=tk&f=7316.7317.7318.7319.7320.7321.7322.40031.7329.40032.7325.7326&a=39560404&app=typekit&e=cssp.typekit.net/p.css?s=1&k=nvp0lhj&h... https://p.typekit.net/p.css?s=1&k=nvp0lhj&ht=tk&f=7316.7317.7318.7319.7320.7321.7322.40031.7329.40032.7325.7326&a=39560404&app=typekit&e=css — 200 — 173 B — 23 ms — h2https://www.wireshark.org/img/hero-background.webpwww.wireshark.org/img/hero-backgrou... https://www.wireshark.org/img/hero-background.webp — 200 — 112.0 KiB — 22 ms — h3https://www.wireshark.org/assets/banners/wcatrainingbanner.pngwww.wireshark.org/assets/banners/wc... https://www.wireshark.org/assets/banners/wcatrainingbanner.png — 200 — 201.2 KiB — 20 ms — h3https://i.ytimg.com/vi_webp/XQvb7bzshcE/maxresdefault.webpi.ytimg.com/vi_webp/XQvb7bzshcE/max... https://i.ytimg.com/vi_webp/XQvb7bzshcE/maxresdefault.webp — 200 — 44.2 KiB — 31 ms — h2https://i.ytimg.com/vi/p0aAt3iB398/maxresdefault.jpgi.ytimg.com/vi/p0aAt3iB398/maxresde... https://i.ytimg.com/vi/p0aAt3iB398/maxresdefault.jpg — 200 — 146.0 KiB — 30 ms — h2https://use.typekit.net/af/5d9976/000000000000000077359bd4/31/l?primer=7cdcb44be4a7db8877ffa5c0007b8dd865b3bbc383831fe2ea177f62257a9191&fvd=n4&v=3use.typekit.net/af/5d9976/000000000... https://use.typekit.net/af/5d9976/000000000000000077359bd4/31/l?primer=7cdcb44be4a7db8877ffa5c0007b8dd865b3bbc383831fe2ea177f62257a9191&fvd=n4&v=3 — 200 — 15.6 KiB — 10 ms — h2https://www.wireshark.org/_astro/wca.C_vSXqTJ_Z2pt6cI.webpwww.wireshark.org/_astro/wca.C_vSXq... https://www.wireshark.org/_astro/wca.C_vSXqTJ_Z2pt6cI.webp — 200 — 80.2 KiB — 18 ms — h3https://www.google-analytics.com/g/collect?v=2&tid=G-YLHRKD6LH6&gtm=45je64h1v9164644227za200zd9164644227&_p=1776800274580&gcd=13l3l3l3l1l1&npa=0&dma=0&are=1&cid=67616564.1776800275&frm=0&pscdl=noapi&rcb=16&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=0~115616986~115938465~115938468~117266400&sid=1776800274&sct=1&seg=0&dl=https%3A%2F%2Fwww.wireshark.org%2F&dt=Wireshark%20%E2%80%A2%20Go%20Deep&en=page_view&_fv=1&_nsi=1&_ss=1&_ee=1&tfd=389www.google-analytics.com/g/collect?... https://www.google-analytics.com/g/collect?v=2&tid=G-YLHRKD6LH6&gtm=45je64h1v9164644227za200zd9164644227&_p=1776800274580&gcd=13l3l3l3l1l1&npa=0&dma=0&are=1&cid=67616564.1776800275&frm=0&pscdl=noapi&rcb=16&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=0~115616986~115938465~115938468~117266400&sid=1776800274&sct=1&seg=0&dl=https%3A%2F%2Fwww.wireshark.org%2F&dt=Wireshark%20%E2%80%A2%20Go%20Deep&en=page_view&_fv=1&_nsi=1&_ss=1&_ee=1&tfd=389 — 204 — 551 B — 41 ms — h2https://cloudflareinsights.com/cdn-cgi/rumcloudflareinsights.com/cdn-cgi/rum https://cloudflareinsights.com/cdn-cgi/rum — 200 — 0 B — 19 ms — h2https://www.wireshark.org/favicon.icowww.wireshark.org/favicon.ico https://www.wireshark.org/favicon.ico — 200 — 4.4 KiB — 20 ms — h3https://cloudflareinsights.com/cdn-cgi/rumcloudflareinsights.com/cdn-cgi/rum https://cloudflareinsights.com/cdn-cgi/rum — 204 — 35 B — 7 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 1163ms · 207KB · €13/mo
www.wireshark.org
Other
Costly
Execution 678ms
Transfer 43 KB
Monthly Cost €7/mo
Google Tag Manager
Tag Manager
Costly
Execution 311ms
Transfer 164 KB
Unused 41%
Monthly Cost €3/mo
Unattributable
Other
Optional
Execution 174ms
Transfer 0 KB
Monthly Cost €2/mo

These scripts may cost more than they're worth

  • www.wireshark.org adds 678ms and costs ~€7/month
  • Google Tag Manager adds 311ms 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

www.wireshark.org takes 678ms 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 311ms 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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