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Performance

· 14 checks — Lighthouse + waterfall + sustainability rolled into one auditable list.
SCORE
88
GRADE
B
FIX
0
REVIEW
2
PASS
10
INFO
2

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

Mobile Desktop
100
Performance Overall performance score (0–100) based on Core Web Vitals and other metrics. 90+ is good.
92
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.
100
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.

489 ms

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

773 ms

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

25 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.

489 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.

1.32 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
10 PASS 2 REVIEW
B
JS Execution Cost
527ms total JS execution
REVIEW
527ms total JS execution
Info::
https://prometheus.io/_next/static/chunks/255-0edc...: 147ms CPU time
Info::
https://prometheus.io/: 103ms CPU time
Info::
https://prometheus.io/_next/static/chunks/341-0544...: 100ms CPU time
Info::
Unattributable: 100ms CPU time
Info::
https://www.googletagmanager.com/gtag/js?id=G-80ZM...: 77ms CPU time
Info::
Third-party scripts: 176ms (33% of total)

Main Thread Breakdown

Script Evaluation 61% Other 15% Script Parsing & Compilation 11% Style & Layout 10%
ScriptTotalScriptingParse/CompileParty
https://prometheus.io/_next/static/chunks/255-0edcbb5b637cbfcb.js147ms136ms5ms1st
https://prometheus.io/103ms4ms7ms1st
https://prometheus.io/_next/static/chunks/341-0544a5ed99d6b02e.js100ms84ms16ms1st
Unattributable100ms20ms0ms3rd
https://www.googletagmanager.com/gtag/js?id=G-80ZM8LGB9677ms61ms15ms3rd
C
JS Bundles
Action
24 scripts, 214 KB unused
REVIEW
24 scripts, 214 KB unused
Warning::
https://prometheus.io/_next/static/chunks/341-0544...: 87 KB unused (61%)
Consider code splitting or tree shaking to reduce unused code.
Warning::
https://www.googletagmanager.com/gtag/js?id=UA-584...: 65 KB unused (57%)
Consider code splitting or tree shaking to reduce unused code.
Warning::
https://www.googletagmanager.com/gtag/js?id=G-80ZM...: 62 KB unused (41%)
Consider code splitting or tree shaking to reduce unused code.
Info::
Total unused JavaScript: 214 KB
214 KB unused JavaScript

Downloaded but never executed on this page.

ScriptSizeUnusedMinifiedParty
https://prometheus.io/_next/static/chunks/341-0544a5ed99d6b02e.js142 KB87 KB (61%)✓1st
https://www.googletagmanager.com/gtag/js?id=UA-58468480-1&cx=c&gtm=4e6460115 KB65 KB (57%)✓3rd
https://www.googletagmanager.com/gtag/js?id=G-80ZM8LGB96152 KB62 KB (41%)✓3rd
https://static.cloudflareinsights.com/beacon.min.js/v8c78df7c7c0f484497ecbca7046644da177152312451611 KB—✓3rd
https://prometheus.io/_next/static/chunks/4bd1b696-409494caf8c83275.js52 KB—✓1st
https://prometheus.io/_next/static/chunks/main-app-95e62da901c4d719.js1 KB—✓1st
https://prometheus.io/_next/static/chunks/619-f072ac750404f9da.js4 KB—✓1st
https://prometheus.io/_next/static/chunks/728-61b6b69bb6f20ba3.js6 KB—✓1st
https://prometheus.io/_next/static/chunks/app/page-f3fe9a5180191228.js3 KB—✓1st
https://prometheus.io/_next/static/chunks/687-55fda7d9c0abd233.js52 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

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
995 KB transferred, 50 requests
PASS
995 KB transferred, 50 requests
Info::
Page weighs 4.4 MB (995 KB transferred)
Warning::
JavaScript is 678 KB — consider code splitting or lazy loading
Large JavaScript bundles delay interactivity. Split code by route or defer non-critical scripts.
Got: 678 KB
Info::
50 HTTP requests
Info::
Estimated 0.20 g CO2 per page load
995 KB / 2.4 MB budget
995 KB transferred
50 requests
0.20 g CO2 per page load
JavaScript 678.0 KiB 68%
Other 199.2 KiB 20%
Fonts 62.0 KiB 6%
CSS 32.7 KiB 3%
HTML 15.4 KiB 2%
Images 5.6 KiB 1%
Other 1.1 KiB 0%
Other 480 B 0%
0 2.4 MB 4.9 MB
Under budget

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

A
Third-Party Impact
30% third-party, 0 ms blocking
PASS
30% third-party, 0 ms blocking
Info::
Third-party code accounts for 30% of page weight (302.0 KiB of 994.6 KiB)
Info::
Third-party blocking time is low (0 ms)
70%
30%
First-party Third-party
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 6 KB
0 oversized -0 KB
3 legacy format
0 missing dimensions CLS risk
A+
Font Loading
2 fonts (62 KB)
PASS
2 fonts (62 KB)
Info::
2 font(s) use font-display: swap (FOUT risk but functional)

Web fonts

2

62 KB total

Render-blocking

0

of 2

Dominant font-display

swap

Most common across fonts

Font loading timeline
Transfer FOIT (block) FOUT (swap)
0 ms 500 ms 1.0 s FCP 489 ms LCP 773 mshttps://prometheus.io/_next/static/media/155cae559bbd1a77-s.p.woff2155cae559bbd1a77-s.p.woff2 https://prometheus.io/_next/static/media/155cae559bbd1a77-s.p.woff2 — 14.2 KiB — 0 ms — font-display: swaphttps://prometheus.io/_next/static/media/e4af272ccee01ff0-s.p.woff2e4af272ccee01ff0-s.p.woff2 https://prometheus.io/_next/static/media/e4af272ccee01ff0-s.p.woff2 — 47.9 KiB — 0 ms — font-display: swap
155cae559bbd1a77-s.p.woff2 woff2 swap
Size 14 KB
Load time 0 ms
Start 0 ms
Risk FOUT — text flashes from fallback to web font
e4af272ccee01ff0-s.p.woff2 woff2 swap
Size 48 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

A
HTTP Caching
max-age=14400 (4 hours)
PASS
max-age=14400 (4 hours)
Info::
Cache-Control header is set
Got: public, max-age=14400, must-revalidate
Info::
Effective TTL: 4 hours (max-age=14400)
Info::
No ETag or Last-Modified header
Conditional requests (304 Not Modified) are not possible without validators.
Cache-Control

public, max-age=14400, must-revalidate

DirectiveValueMeaning
public—Any cache may store this response
max-age14400Cache for 4 hours
must-revalidate—Must recheck with server after expiry
Effective TTL: 14400 seconds
Network Waterfall
50 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
33% of JavaScript execution is third-party
First-party Third-party 176ms · 152KB · $2/mo
Unattributable
Other
Optional
Execution 100ms
Transfer 0 KB
Monthly Cost $1/mo
Google Tag Manager
Tag Manager
Optional
Execution 77ms
Transfer 152 KB
Unused 41%
Monthly Cost $1/mo

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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