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Performance

· 16 checks — Lighthouse + waterfall + sustainability rolled into one auditable list.
SCORE
95
GRADE
A
FIX
1
REVIEW
2
PASS
11
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.
91
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.
91
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.

1.27 s

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

2.89 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.

2.32 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.

2.89 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
16
11 PASS 2 REVIEW 1 FIX
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.

B
Third-Party Impact
42% third-party, 0 ms blocking
REVIEW
42% third-party, 0 ms blocking
Info::
Third-party code accounts for 42% of page weight (77.3 KiB of 183.6 KiB)
Info::
Third-party blocking time is low (0 ms)
58%
42%
First-party Third-party
C
Green Hosting
Action
Whether the site is served from green-energy infrastructure
REVIEW

Green Hosting

No green hosting detected

A+
Page Weight Budget
184 KB transferred, 12 requests
PASS
184 KB transferred, 12 requests
Info::
Page weighs 358 KB (184 KB transferred)
Info::
12 HTTP requests
Info::
Estimated 0.04 g CO2 per page load
184 KB / 2.4 MB budget
184 KB transferred
12 requests
0.04 g CO2 per page load
JavaScript 82.9 KiB 45%
Images 72.3 KiB 39%
CSS 20.9 KiB 11%
Other 3.6 KiB 2%
HTML 2.6 KiB 1%
Other 1.4 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
Image Optimization
3 images, 0 KB saveable
PASS
3 images, 0 KB saveable
Info::
All images are well-optimized
3 images 72 KB
0 oversized -0 KB
3 legacy format
0 missing dimensions CLS risk
A+
JS Execution Cost
326ms total JS execution
PASS
326ms total JS execution
Info::
https://www.r-project.org/: 142ms CPU time
Info::
Unattributable: 128ms CPU time
Info::
https://ajax.googleapis.com/ajax/libs/jquery/1.11....: 56ms CPU time
Warning::
Third-party scripts: 184ms (57% of total)

Main Thread Breakdown

Other 38% Style & Layout 29% Script Evaluation 19% Script Parsing & Compilation 7% Parse HTML & CSS 6%
ScriptTotalScriptingParse/CompileParty
https://www.r-project.org/142ms4ms1ms1st
Unattributable128ms9ms0ms3rd
https://ajax.googleapis.com/ajax/libs/jquery/1.11.1/jquery.min.js56ms37ms15ms3rd
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
JS Bundles
3 scripts, 49 KB unused
PASS
3 scripts, 49 KB unused
Warning::
https://www.r-project.org/js/bootstrap.min.js: 28 KB unused (81%)
Consider code splitting or tree shaking to reduce unused code.
Warning::
https://ajax.googleapis.com/ajax/libs/jquery/1.11....: 21 KB unused (65%)
Consider code splitting or tree shaking to reduce unused code.
Warning::
https://www.r-project.org/mastodon-timeline.js: unminified — 6 KB could be saved
Info::
Total unused JavaScript: 49 KB
49 KB unused JavaScript

Downloaded but never executed on this page.

ScriptSizeUnusedMinifiedParty
https://www.r-project.org/js/bootstrap.min.js35 KB28 KB (81%)✓1st
https://ajax.googleapis.com/ajax/libs/jquery/1.11.1/jquery.min.js33 KB21 KB (65%)✓3rd
https://www.r-project.org/mastodon-timeline.js15 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

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+
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
12 requests over 0ms
INFO

Performance analysis not available for this result.

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 184ms · 33KB · €2/mo
Unattributable
Other
Optional
Execution 128ms
Transfer 0 KB
Monthly Cost €1/mo
ajax.googleapis.com
Other
Optional
Execution 56ms
Transfer 33 KB
Unused 65%
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

65% of ajax.googleapis.com'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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