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Performance

· 14 checks — Lighthouse + waterfall + sustainability rolled into one auditable list.
SCORE
80
GRADE
B
FIX
2
REVIEW
4
PASS
6
INFO
2

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

Mobile Desktop
97
Performance Overall performance score (0–100) based on Core Web Vitals and other metrics. 90+ is good.
85
Accessibility Measures how accessible the page is for users with disabilities. Checks color contrast, ARIA labels, and semantic HTML.
73
Best Practices Checks for modern web development best practices including HTTPS, no console errors, and secure JavaScript.
85
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.

586 ms

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

1.27 s

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

6 ms

Cumulative Layout Shift Cumulative Layout Shift — measures visual stability. How much the page layout shifts during loading. Under 0.1 is good.

0.024

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

804 ms

Time to Interactive Time to Interactive — how long until the page is fully interactive and responds to user input. Under 3.8s is good.

2.12 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
14
6 PASS 4 REVIEW 2 FIX
D
Third-Party Impact
Action
62% third-party, 0 ms blocking
FIX
62% third-party, 0 ms blocking
Warning::
Third-party code accounts for 62% of page weight (731.4 KiB of 1.2 MiB)
Info::
Third-party blocking time is low (0 ms)
38%
62%
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
Page Weight Budget
1.2 MB transferred, 78 requests
REVIEW
1.2 MB transferred, 78 requests
Info::
Page weighs 2.7 MB (1.2 MB transferred)
Info::
78 HTTP requests
Info::
Estimated 0.24 g CO2 per page load
1.2 MB / 2.4 MB budget
1.2 MB transferred
78 requests
0.24 g CO2 per page load
JavaScript 484.2 KiB 41%
Images 450.2 KiB 38%
Fonts 113.3 KiB 10%
CSS 62.4 KiB 5%
HTML 39.1 KiB 3%
Other 33.6 KiB 3%
Other 1.9 KiB 0%
Other 838 B 0%
Other 464 B 0%
0 2.4 MB 4.9 MB
Under budget
C
Image Optimization
Action
28 images, 0 KB saveable
REVIEW
28 images, 0 KB saveable
Warning::
https://secure.gravatar.com/avatar/6bc7516fbadd709... is missing width/height — may cause layout shift
Set explicit width and height to prevent CLS.
Warning::
https://secure.gravatar.com/avatar/0bb46f96dd1a017... is missing width/height — may cause layout shift
Set explicit width and height to prevent CLS.
Warning::
https://secure.gravatar.com/avatar/a8e040142716a4b... is missing width/height — may cause layout shift
Set explicit width and height to prevent CLS.
Warning::
https://secure.gravatar.com/avatar/c16ca31febf1ccf... is missing width/height — may cause layout shift
Set explicit width and height to prevent CLS.
Warning::
https://consent.trustarc.com/get?name=css-tricks.c... is missing width/height — may cause layout shift
Set explicit width and height to prevent CLS.
Warning::
https://secure.gravatar.com/avatar/b6c928ce1b901c3... is missing width/height — may cause layout shift
Set explicit width and height to prevent CLS.
Warning::
https://secure.gravatar.com/avatar/db5b77793bb2e05... is missing width/height — may cause layout shift
Set explicit width and height to prevent CLS.
28 images 450 KB
0 oversized -0 KB
17 legacy format
7 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

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
637ms total JS execution
REVIEW
637ms total JS execution
Warning::
https://css-tricks.com/: 336ms CPU time
Info::
Unattributable: 235ms CPU time
Info::
https://www.googletagmanager.com/gtag/js?id=G-4TM4...: 66ms CPU time
Info::
Third-party scripts: 301ms (47% of total)

Main Thread Breakdown

Script Evaluation 33% Other 24% Style & Layout 24% Script Parsing & Compilation 6% Parse HTML & CSS 5% Rendering 5% Garbage Collection 3%
ScriptTotalScriptingParse/CompileParty
https://css-tricks.com/336ms8ms4ms1st
Unattributable235ms33ms0ms3rd
https://www.googletagmanager.com/gtag/js?id=G-4TM4ZB5G5N&cx=c&_slc=166ms49ms17ms3rd
B
JS Bundles
29 scripts, 110 KB unused
REVIEW
29 scripts, 110 KB unused
Warning::
https://www.googletagmanager.com/gtag/js?id=G-4TM4...: 69 KB unused (42%)
Consider code splitting or tree shaking to reduce unused code.
Warning::
https://consent.trustarc.com/asset/notice.js/v/v1....: 21 KB unused (59%)
Consider code splitting or tree shaking to reduce unused code.
Warning::
https://css-tricks.com/wp-content/themes/CSS-Trick...: 20 KB unused (61%)
Consider code splitting or tree shaking to reduce unused code.
Info::
Total unused JavaScript: 110 KB
110 KB unused JavaScript

Downloaded but never executed on this page.

ScriptSizeUnusedMinifiedParty
https://www.googletagmanager.com/gtag/js?id=G-4TM4ZB5G5N&cx=c&_slc=1166 KB69 KB (42%)✓3rd
https://consent.trustarc.com/asset/notice.js/v/v1.7-854936 KB21 KB (59%)✓3rd
https://css-tricks.com/wp-content/themes/CSS-Tricks-19/js/min/jquery-3.5.1.min.js33 KB20 KB (61%)✓1st
https://css-tricks.com/wp-content/plugins/gravityforms/js/gravityforms.min.js?ver=2.9.3114 KB—✓1st
https://css-tricks.com/wp-content/plugins/gravityforms/assets/js/dist/utils.min.js?ver=3f278756f0a3032bed328ff6a9f6c01d18 KB—✓1st
https://c0.wp.com/c/6.9.4/wp-includes/js/dist/vendor/wp-polyfill.min.js12 KB—✓3rd
https://c0.wp.com/c/6.9.4/wp-includes/js/dist/url.min.js4 KB—✓3rd
https://css-tricks.com/wp-content/plugins/jetpack/jetpack_vendor/automattic/jetpack-search/build/instant-search/jp-search.js?minify=false&ver=c6f0bb58d03d6acccc5b3 KB—✓1st
https://stats.wp.com/w.js?ver=2026145 KB—✓3rd
https://c0.wp.com/c/6.9.4/wp-includes/js/dist/i18n.min.js3 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

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 (113 KB)
PASS
3 fonts (113 KB)
Info::
3 font(s) use font-display: swap (FOUT risk but functional)

Web fonts

3

113 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 500 ms 1.0 s FCP 586 ms LCP 1.3 shttps://css-tricks.com/wp-content/themes/CSS-Tricks-19/fonts/BlancoSubset-Regular.woff2BlancoSubset-Regular.woff2 https://css-tricks.com/wp-content/themes/CSS-Tricks-19/fonts/BlancoSubset-Regular.woff2 — 41.5 KiB — 0 ms — font-display: swaphttps://css-tricks.com/wp-content/themes/CSS-Tricks-19/fonts/MDPrimer-Bold.woff2MDPrimer-Bold.woff2 https://css-tricks.com/wp-content/themes/CSS-Tricks-19/fonts/MDPrimer-Bold.woff2 — 27.1 KiB — 0 ms — font-display: swaphttps://css-tricks.com/wp-content/themes/CSS-Tricks-19/fonts/BlancoSubset-Bold.woff2BlancoSubset-Bold.woff2 https://css-tricks.com/wp-content/themes/CSS-Tricks-19/fonts/BlancoSubset-Bold.woff2 — 44.6 KiB — 0 ms — font-display: swap
BlancoSubset-Regular.woff2 woff2 swap
Size 42 KB
Load time 0 ms
Start 0 ms
Risk FOUT — text flashes from fallback to web font
MDPrimer-Bold.woff2 woff2 swap
Size 27 KB
Load time 0 ms
Start 0 ms
Risk FOUT — text flashes from fallback to web font
BlancoSubset-Bold.woff2 woff2 swap
Size 45 KB
Load time 0 ms
Start 0 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+
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
78 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
47% of JavaScript execution is third-party
First-party Third-party 301ms · 166KB · €2/mo
Unattributable
Other
Costly
Execution 235ms
Transfer 0 KB
Monthly Cost €1/mo
Google Tag Manager
Tag Manager
Optional
Execution 66ms
Transfer 166 KB
Unused 42%
Monthly Cost €0/mo

These scripts may cost more than they're worth

  • Unattributable adds 235ms and costs ~€1/month

47% 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

Unattributable takes 235ms 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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