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Performance

· 16 checks — Lighthouse + waterfall + sustainability rolled into one auditable list.
SCORE
77
GRADE
C
FIX
3
REVIEW
4
PASS
7
INFO
2

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

Mobile Desktop
54
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.
73
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.

1.41 s

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

4.74 s

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

2.02 s

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

0.009

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

3.56 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.

16.26 s

Page Load Progression

717 ms
1.4 s
2.2 s
2.9 s
3.6 s
4.3 s
5.0 s
5.7 s
Checks
16
7 PASS 4 REVIEW 3 FIX
D
Third-Party Impact
Action
61% third-party, 0 ms blocking
FIX
61% third-party, 0 ms blocking
Warning::
Third-party code accounts for 61% of page weight (1.2 MiB of 1.9 MiB)
Info::
Third-party blocking time is low (0 ms)
39%
61%
First-party Third-party
F
JS Execution Cost
Action
7334ms total JS execution
FIX
7334ms total JS execution
Warning::
https://www.prefect.io/: 1197ms CPU time
Warning::
Unattributable: 1179ms CPU time
Warning::
https://www.prefect.io/_next/static/chunks/d6c3161...: 1116ms CPU time
Warning::
https://www.gstatic.com/recaptcha/releases/kUYUkUl...: 653ms CPU time
Warning::
https://cdn.cookielaw.org/scripttemplates/202304.1...: 634ms CPU time
Warning::
Third-party scripts: 4881ms (67% of total)

Main Thread Breakdown

Script Evaluation 52% Other 21% Script Parsing & Compilation 13% Style & Layout 7% Rendering 3%
ScriptTotalScriptingParse/CompileParty
https://www.prefect.io/1197ms23ms25ms1st
Unattributable1179ms281ms0ms3rd
https://www.prefect.io/_next/static/chunks/d6c3161eafdca609.js?dpl=dpl_28dSMm69PiuKWBPr3J369Wae9e1H1116ms863ms28ms1st
https://www.gstatic.com/recaptcha/releases/kUYUkUlSyqkjTSMaN2w3RaOh/recaptcha__en.js653ms269ms383ms3rd
https://cdn.cookielaw.org/scripttemplates/202304.1.0/otBannerSdk.js634ms395ms149ms3rd
https://www.redditstatic.com/ads/pixel.js454ms414ms8ms3rd
https://www.googletagmanager.com/gtm.js?id=GTM-N633BZ8450ms375ms66ms3rd
https://www.googletagmanager.com/gtag/js?id=G-CP29SJK4E7&cx=c&gtm=4e6460424ms349ms68ms3rd
https://www.googletagmanager.com/gtag/js?id=AW-662873615&cx=c&gtm=4e6460414ms319ms50ms3rd
https://d-code.liadm.com/did-006l.min.js305ms212ms68ms3rd

Showing top 10 of 16 scripts

F
JS Bundles
Action
40 scripts, 632 KB unused
FIX
40 scripts, 632 KB unused
Warning::
https://www.gstatic.com/recaptcha/releases/kUYUkUl...: 245 KB unused (68%)
Consider code splitting or tree shaking to reduce unused code.
Warning::
https://www.googletagmanager.com/gtag/js?id=G-CP29...: 65 KB unused (37%)
Consider code splitting or tree shaking to reduce unused code.
Warning::
https://www.googletagmanager.com/gtm.js?id=GTM-N63...: 63 KB unused (38%)
Consider code splitting or tree shaking to reduce unused code.
Warning::
https://www.googletagmanager.com/gtag/js?id=AW-662...: 53 KB unused (36%)
Consider code splitting or tree shaking to reduce unused code.
Warning::
https://cdn.cookielaw.org/scripttemplates/202304.1...: 52 KB unused (53%)
Consider code splitting or tree shaking to reduce unused code.
Info::
Total unused JavaScript: 632 KB
632 KB unused JavaScript

Downloaded but never executed on this page.

ScriptSizeUnusedMinifiedParty
https://www.gstatic.com/recaptcha/releases/kUYUkUlSyqkjTSMaN2w3RaOh/recaptcha__en.js363 KB245 KB (68%)✓3rd
https://www.googletagmanager.com/gtag/js?id=G-CP29SJK4E7&cx=c&gtm=4e6460177 KB65 KB (37%)✓3rd
https://www.googletagmanager.com/gtm.js?id=GTM-N633BZ8167 KB63 KB (38%)✓3rd
https://www.googletagmanager.com/gtag/js?id=AW-662873615&cx=c&gtm=4e6460146 KB53 KB (36%)✓3rd
https://cdn.cookielaw.org/scripttemplates/202304.1.0/otBannerSdk.js97 KB52 KB (53%)✓3rd
https://www.prefect.io/_next/static/chunks/0d62aab73d9e3e4a.js?dpl=dpl_28dSMm69PiuKWBPr3J369Wae9e1H43 KB38 KB (88%)✓1st
https://d-code.liadm.com/did-006l.min.js47 KB33 KB (71%)✓3rd
https://www.prefect.io/_next/static/chunks/fb74acd3f9a622b8.js?dpl=dpl_28dSMm69PiuKWBPr3J369Wae9e1H46 KB31 KB (69%)✓1st
https://www.prefect.io/_next/static/chunks/d68e5a1c93cc72e7.js?dpl=dpl_28dSMm69PiuKWBPr3J369Wae9e1H27 KB27 KB (100%)✓1st
https://www.prefect.io/_next/static/chunks/d6c3161eafdca609.js?dpl=dpl_28dSMm69PiuKWBPr3J369Wae9e1H70 KB25 KB (35%)✓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

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

C
Page Weight Budget
Action
1.9 MB transferred, 148 requests
REVIEW
1.9 MB transferred, 148 requests
Info::
Page weighs 5.4 MB (1.9 MB transferred)
Warning::
JavaScript is 1.4 MB — consider code splitting or lazy loading
Large JavaScript bundles delay interactivity. Split code by route or defer non-critical scripts.
Got: 1.4 MB
Warning::
148 HTTP requests — consider bundling or reducing
Each request adds latency. Bundle small files, use sprites, or eliminate unnecessary requests.
Info::
Estimated 0.40 g CO2 per page load
1.9 MB / 2.4 MB budget
1.9 MB transferred
148 requests
0.40 g CO2 per page load
JavaScript 1.4 MiB 75%
Images 265.6 KiB 14%
Other 76.6 KiB 4%
Fonts 65.4 KiB 3%
CSS 52.3 KiB 3%
HTML 24.0 KiB 1%
Other 4.5 KiB 0%
Other 4.4 KiB 0%
Other 722 B 0%
Other 0 B 0%
0 2.4 MB 4.9 MB
Approaching limit

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

Each request adds latency. Bundle small files, use sprites, or eliminate unnecessary requests.

Why this matters

High HTTP request count — bundling, sprite-ing, and HTTP/2 server push can reduce per-request overhead.

Source: web.dev

B
Image Optimization
40 images, 0 KB saveable
REVIEW
40 images, 0 KB saveable
Info::
All images are well-optimized
40 images 266 KB
0 oversized -0 KB
26 legacy format
0 missing dimensions CLS risk
C
Green Hosting
Action
Whether the site is served from green-energy infrastructure
REVIEW

Green Hosting

No green hosting detected

B
HTTP Caching
public, max-age=0, must-revalidate
REVIEW
public, max-age=0, must-revalidate
Info::
Cache-Control header is set
Got: public, max-age=0, must-revalidate
Info::
ETag present — enables conditional (304) responses
Cache-Control

public, max-age=0, must-revalidate

DirectiveValueMeaning
public—Any cache may store this response
max-age0Cache for 0 seconds
must-revalidate—Must recheck with server after expiry
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
4 fonts (65 KB)
PASS
4 fonts (65 KB)
Info::
4 font(s) use font-display: swap (FOUT risk but functional)

Web fonts

4

65 KB total

Render-blocking

0

of 4

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 1.4 s LCP 4.7 shttps://www.prefect.io/_next/static/media/caa3a2e1cccd8315-s.p.853070df.woff2caa3a2e1cccd8315-s.p.85... https://www.prefect.io/_next/static/media/caa3a2e1cccd8315-s.p.853070df.woff2 — 28.0 KiB — 0 ms — font-display: swaphttps://www.prefect.io/fonts/ArticulatCF-DemiBold.woff2ArticulatCF-DemiBold.woff2 https://www.prefect.io/fonts/ArticulatCF-DemiBold.woff2 — 16.5 KiB — 0 ms — font-display: swaphttps://www.prefect.io/fonts/ArticulatCF-Regular.woff2ArticulatCF-Regular.woff2 https://www.prefect.io/fonts/ArticulatCF-Regular.woff2 — 16.2 KiB — 0 ms — font-display: swaphttps://www.prefect.io/fonts/AeonikMonoTRIAL-Regular.woff2AeonikMonoTRIAL-Regular... https://www.prefect.io/fonts/AeonikMonoTRIAL-Regular.woff2 — 4.7 KiB — 0 ms — font-display: swap
caa3a2e1cccd8315-s.p.85... woff2 swap
Size 28 KB
Load time 0 ms
Start 0 ms
Risk FOUT — text flashes from fallback to web font
ArticulatCF-DemiBold.woff2 woff2 swap
Size 17 KB
Load time 0 ms
Start 0 ms
Risk FOUT — text flashes from fallback to web font
ArticulatCF-Regular.woff2 woff2 swap
Size 16 KB
Load time 0 ms
Start 0 ms
Risk FOUT — text flashes from fallback to web font
AeonikMonoTRIAL-Regular... woff2 swap
Size 5 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
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+
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
148 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
67% of JavaScript execution is third-party
First-party Third-party 4881ms · 1081KB · $84/mo
Unattributable
Other
Costly
Execution 1179ms
Transfer 0 KB
Monthly Cost $20/mo
www.gstatic.com
Other
Costly
Execution 653ms
Transfer 363 KB
Unused 68%
Monthly Cost $11/mo
OneTrust
Consent
Essential
Execution 634ms
Transfer 97 KB
Unused 53%
Monthly Cost $11/mo
www.redditstatic.com
Other
Costly
Execution 454ms
Transfer 19 KB
Monthly Cost $8/mo
Google Tag Manager
Tag Manager
Costly
Execution 450ms
Transfer 167 KB
Unused 38%
Monthly Cost $8/mo
Google Tag Manager
Tag Manager
Costly
Execution 424ms
Transfer 177 KB
Unused 37%
Monthly Cost $7/mo
Google Tag Manager
Tag Manager
Costly
Execution 414ms
Transfer 146 KB
Unused 36%
Monthly Cost $7/mo
d-code.liadm.com
Other
Costly
Execution 305ms
Transfer 47 KB
Unused 71%
Monthly Cost $5/mo
LinkedIn Insight
Advertising
Optional
Execution 99ms
Transfer 19 KB
Monthly Cost $2/mo
Twitter/X Pixel
Advertising
Optional
Execution 89ms
Transfer 13 KB
Monthly Cost $2/mo
OneTrust
Consent
Essential
Execution 68ms
Transfer 9 KB
Monthly Cost $1/mo
cdn.vector.co
Other
Optional
Execution 55ms
Transfer 16 KB
Monthly Cost $1/mo
OneTrust
Consent
Essential
Execution 55ms
Transfer 9 KB
Monthly Cost $1/mo

These scripts may cost more than they're worth

  • Unattributable adds 1179ms and costs ~$20/month
  • www.gstatic.com adds 653ms and costs ~$11/month
  • www.redditstatic.com adds 454ms and costs ~$8/month
  • Google Tag Manager adds 450ms and costs ~$8/month
  • Google Tag Manager adds 424ms and costs ~$7/month
  • Google Tag Manager adds 414ms and costs ~$7/month
  • d-code.liadm.com adds 305ms and costs ~$5/month

67% 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 1179ms 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

www.gstatic.com takes 653ms 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

68% of www.gstatic.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

53% of OneTrust'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

www.redditstatic.com takes 454ms 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 450ms 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 424ms 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 414ms 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

d-code.liadm.com takes 305ms 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

71% of d-code.liadm.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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