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Performance

· 16 checks — Lighthouse + waterfall + sustainability rolled into one auditable list.
SCORE
74
GRADE
C
FIX
5
REVIEW
2
PASS
7
INFO
2

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

Mobile Desktop
38
Performance Overall performance score (0–100) based on Core Web Vitals and other metrics. 90+ is good.
97
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.
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.

2.91 s

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

13.96 s

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

2.36 s

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

0.028

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

4.96 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.

18.96 s

Page Load Progression

1.1 s
2.1 s
3.2 s
4.2 s
5.3 s
6.3 s
7.4 s
8.5 s
Checks
16
7 PASS 2 REVIEW 5 FIX
D
Page Weight Budget
Action
2.4 MB transferred, 134 requests
FIX
2.4 MB transferred, 134 requests
Info::
Page weighs 7.7 MB (2.4 MB transferred)
Warning::
JavaScript is 1.8 MB — consider code splitting or lazy loading
Large JavaScript bundles delay interactivity. Split code by route or defer non-critical scripts.
Got: 1.8 MB
Warning::
134 HTTP requests — consider bundling or reducing
Each request adds latency. Bundle small files, use sprites, or eliminate unnecessary requests.
Info::
Estimated 0.51 g CO2 per page load
2.4 MB / 2.4 MB budget
2.4 MB transferred
134 requests
0.51 g CO2 per page load
JavaScript 1.8 MiB 72%
Images 518.2 KiB 21%
HTML 102.9 KiB 4%
Fonts 28.7 KiB 1%
Other 15.6 KiB 1%
CSS 7.8 KiB 0%
Other 6.3 KiB 0%
Other 4.2 KiB 0%
Other 1.6 KiB 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

D
Third-Party Impact
Action
95% third-party, 0 ms blocking
FIX
95% third-party, 0 ms blocking
Warning::
Third-party code accounts for 95% of page weight (2.3 MiB of 2.4 MiB)
Info::
Third-party blocking time is low (0 ms)
95%
First-party Third-party
F
JS Execution Cost
Action
10177ms total JS execution
FIX
10177ms total JS execution
Warning::
https://d3njjcbhbojbot.cloudfront.net/webapps/r2-b...: 3611ms CPU time
Warning::
https://www.coursera.org/: 3440ms CPU time
Warning::
Unattributable: 905ms CPU time
Warning::
https://d3njjcbhbojbot.cloudfront.net/webapps/r2-b...: 659ms CPU time
Warning::
https://www.googletagmanager.com/gtm.js?id=GTM-5JK...: 630ms CPU time
Warning::
Third-party scripts: 6738ms (66% of total)

Main Thread Breakdown

Script Evaluation 46% Other 24% Rendering 12% Style & Layout 8% Script Parsing & Compilation 7%
ScriptTotalScriptingParse/CompileParty
https://d3njjcbhbojbot.cloudfront.net/webapps/r2-builds/br/front-page/en.app.065b0df2eb410c5e1c70.js3611ms3160ms160ms3rd
https://www.coursera.org/3440ms55ms28ms1st
Unattributable905ms27ms0ms3rd
https://d3njjcbhbojbot.cloudfront.net/webapps/r2-builds/br/front-page/en.14.f1452cee01d415df84ac.js659ms485ms137ms3rd
https://www.googletagmanager.com/gtm.js?id=GTM-5JKLVK&l=dataLayer630ms511ms103ms3rd
https://browser.sentry-cdn.com/7.116.0/bundle.tracing.min.js340ms126ms8ms3rd
https://www.googletagmanager.com/gtag/destination?id=AW-927621030&cx=c&gtm=4e6460279ms237ms40ms3rd
https://www.googletagmanager.com/gtag/js?id=AW-11173242093&cx=c&gtm=4e6460132ms99ms32ms3rd
https://d3njjcbhbojbot.cloudfront.net/webapps/r2-builds/br/front-page/13.0842390ff078322547ec.js117ms2ms114ms3rd
https://accounts.google.com/gsi/client64ms44ms19ms3rd
F
JS Bundles
Action
26 scripts, 699 KB unused
FIX
26 scripts, 699 KB unused
Warning::
https://d3njjcbhbojbot.cloudfront.net/webapps/r2-b...: 153 KB unused (36%)
Consider code splitting or tree shaking to reduce unused code.
Warning::
https://d3njjcbhbojbot.cloudfront.net/webapps/r2-b...: 113 KB unused (49%)
Consider code splitting or tree shaking to reduce unused code.
Warning::
https://d3njjcbhbojbot.cloudfront.net/webapps/r2-b...: 102 KB unused (36%)
Consider code splitting or tree shaking to reduce unused code.
Warning::
https://www.googletagmanager.com/gtm.js?id=GTM-5JK...: 71 KB unused (31%)
Consider code splitting or tree shaking to reduce unused code.
Warning::
https://accounts.google.com/gsi/client: 70 KB unused (76%)
Consider code splitting or tree shaking to reduce unused code.
Info::
Total unused JavaScript: 699 KB
699 KB unused JavaScript

Downloaded but never executed on this page.

ScriptSizeUnusedMinifiedParty
https://d3njjcbhbojbot.cloudfront.net/webapps/r2-builds/br/front-page/en.app.065b0df2eb410c5e1c70.js429 KB153 KB (36%)✓3rd
https://d3njjcbhbojbot.cloudfront.net/webapps/r2-builds/br/front-page/13.0842390ff078322547ec.js235 KB113 KB (49%)✓3rd
https://d3njjcbhbojbot.cloudfront.net/webapps/r2-builds/br/front-page/en.14.f1452cee01d415df84ac.js287 KB102 KB (36%)✓3rd
https://www.googletagmanager.com/gtm.js?id=GTM-5JKLVK&l=dataLayer227 KB71 KB (31%)✓3rd
https://accounts.google.com/gsi/client94 KB70 KB (76%)✓3rd
https://www.googletagmanager.com/gtag/destination?id=AW-927621030&cx=c&gtm=4e6460139 KB68 KB (49%)✓3rd
https://www.googletagmanager.com/gtag/js?id=AW-11173242093&cx=c&gtm=4e6460139 KB62 KB (45%)✓3rd
https://browser.sentry-cdn.com/7.116.0/bundle.tracing.min.js110 KB60 KB (54%)✓3rd
https://d3njjcbhbojbot.cloudfront.net/webapps/r2-builds/br/front-page/1.d2268f2ea683a4c6989b.js25 KB—✓3rd
https://d3njjcbhbojbot.cloudfront.net/webapps/r2-builds/br/front-page/en.6.78306b0eb46f49a1116b.js5 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

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

D
HTTP Caching
Action
no-store (uncacheable)
FIX
no-store (uncacheable)
Info::
Cache-Control: no-store prevents all caching
Intentional for dynamic content, but increases server load for every page view.
Got: private, no-cache, no-store, must-revalidate, max-age=0
Info::
ETag present — enables conditional (304) responses
Cache-Control

private, no-cache, no-store, must-revalidate, max-age=0

DirectiveValueMeaning
private—Only browser cache, not CDN/proxy
no-cache—Cache but always revalidate first
no-store—Never cache this response
must-revalidate—Must recheck with server after expiry
max-age0Cache for 0 seconds
C
Image Optimization
Action
75 images, 0 KB saveable
REVIEW
75 images, 0 KB saveable
Warning::
https://d3njjcbhbojbot.cloudfront.net/api/utilitie... is missing width/height — may cause layout shift
Set explicit width and height to prevent CLS.
Warning::
https://d3njjcbhbojbot.cloudfront.net/api/utilitie... is missing width/height — may cause layout shift
Set explicit width and height to prevent CLS.
Warning::
https://d3njjcbhbojbot.cloudfront.net/api/utilitie... is missing width/height — may cause layout shift
Set explicit width and height to prevent CLS.
Warning::
https://d3njjcbhbojbot.cloudfront.net/api/utilitie... is missing width/height — may cause layout shift
Set explicit width and height to prevent CLS.
Warning::
https://d3njjcbhbojbot.cloudfront.net/api/utilitie... is missing width/height — may cause layout shift
Set explicit width and height to prevent CLS.
Warning::
https://d3njjcbhbojbot.cloudfront.net/api/utilitie... is missing width/height — may cause layout shift
Set explicit width and height to prevent CLS.
Warning::
https://d3njjcbhbojbot.cloudfront.net/api/utilitie... is missing width/height — may cause layout shift
Set explicit width and height to prevent CLS.
Warning::
https://d3njjcbhbojbot.cloudfront.net/api/utilitie... is missing width/height — may cause layout shift
Set explicit width and height to prevent CLS.
Warning::
https://d3njjcbhbojbot.cloudfront.net/api/utilitie... is missing width/height — may cause layout shift
Set explicit width and height to prevent CLS.
Warning::
https://d3njjcbhbojbot.cloudfront.net/api/utilitie... is missing width/height — may cause layout shift
Set explicit width and height to prevent CLS.
Warning::
https://d3njjcbhbojbot.cloudfront.net/api/utilitie... is missing width/height — may cause layout shift
Set explicit width and height to prevent CLS.
Warning::
https://d3njjcbhbojbot.cloudfront.net/api/utilitie... is missing width/height — may cause layout shift
Set explicit width and height to prevent CLS.
Warning::
https://d3njjcbhbojbot.cloudfront.net/api/utilitie... is missing width/height — may cause layout shift
Set explicit width and height to prevent CLS.
Warning::
https://d3njjcbhbojbot.cloudfront.net/api/utilitie... is missing width/height — may cause layout shift
Set explicit width and height to prevent CLS.
Warning::
https://d3njjcbhbojbot.cloudfront.net/api/utilitie... is missing width/height — may cause layout shift
Set explicit width and height to prevent CLS.
75 images 518 KB
0 oversized -0 KB
75 legacy format
15 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

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

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

C
Green Hosting
Action
Whether the site is served from green-energy infrastructure
REVIEW

Green Hosting

No green hosting detected

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
1 fonts (29 KB)
PASS
1 fonts (29 KB)
Info::
1 font(s) use font-display: swap (FOUT risk but functional)

Web fonts

1

29 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 2.0 s 4.0 s 6.0 s 8.0 s 10.0 s 12.0 s 14.0 s FCP 2.9 s LCP 14.0 shttps://d3njjcbhbojbot.cloudfront.net/web/type/source-sans-3-optimized/ss3-latin-normal.woff2ss3-latin-normal.woff2 https://d3njjcbhbojbot.cloudfront.net/web/type/source-sans-3-optimized/ss3-latin-normal.woff2 — 28.7 KiB — 0 ms — font-display: swap
ss3-latin-normal.woff2 woff2 swap
Size 29 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
7 hints, 0 missing preconnects
PASS
7 hints, 0 missing preconnects
Info::
Page uses 7 resource hint(s)

Current Resource Hints

preconnect
2
preload
5
dns-prefetch
—
prefetch
—

7 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
134 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
66% of JavaScript execution is third-party
First-party Third-party 6738ms · 1658KB · €108/mo
d3njjcbhbojbot.cloudfront.net
Other
Costly
Execution 3611ms
Transfer 429 KB
Unused 36%
Monthly Cost €58/mo
Unattributable
Other
Costly
Execution 905ms
Transfer 0 KB
Monthly Cost €14/mo
d3njjcbhbojbot.cloudfront.net
Other
Costly
Execution 659ms
Transfer 287 KB
Unused 36%
Monthly Cost €11/mo
Google Tag Manager
Tag Manager
Costly
Execution 630ms
Transfer 227 KB
Unused 31%
Monthly Cost €10/mo
browser.sentry-cdn.com
Other
Costly
Execution 340ms
Transfer 110 KB
Unused 54%
Monthly Cost €5/mo
Google Tag Manager
Tag Manager
Costly
Execution 279ms
Transfer 139 KB
Unused 49%
Monthly Cost €4/mo
Google Tag Manager
Tag Manager
Optional
Execution 132ms
Transfer 139 KB
Unused 45%
Monthly Cost €2/mo
d3njjcbhbojbot.cloudfront.net
Other
Optional
Execution 117ms
Transfer 235 KB
Unused 49%
Monthly Cost €2/mo
accounts.google.com
Other
Optional
Execution 64ms
Transfer 94 KB
Unused 76%
Monthly Cost €1/mo

These scripts may cost more than they're worth

  • d3njjcbhbojbot.cloudfront.net adds 3611ms and costs ~€58/month
  • Unattributable adds 905ms and costs ~€14/month
  • d3njjcbhbojbot.cloudfront.net adds 659ms and costs ~€11/month
  • Google Tag Manager adds 630ms and costs ~€10/month
  • browser.sentry-cdn.com adds 340ms and costs ~€5/month
  • Google Tag Manager adds 279ms and costs ~€4/month

66% 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

d3njjcbhbojbot.cloudfront.net takes 3611ms 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

Unattributable takes 905ms 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

d3njjcbhbojbot.cloudfront.net takes 659ms 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 630ms 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

browser.sentry-cdn.com takes 340ms 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

54% of browser.sentry-cdn.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

Google Tag Manager takes 279ms 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

76% of accounts.google.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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