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Performance

· 16 checks — Lighthouse + waterfall + sustainability rolled into one auditable list.
SCORE
77
GRADE
C
FIX
3
REVIEW
2
PASS
9
INFO
2

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

Mobile Desktop
32
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.
77
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.

6.01 s

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

20.70 s

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

1.37 s

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.

9.01 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.

20.98 s

Page Load Progression

533 ms
1.1 s
1.6 s
2.1 s
2.7 s
3.2 s
3.7 s
4.3 s
Checks
16
9 PASS 2 REVIEW 3 FIX
F
Page Weight Budget
Action
2.8 MB transferred, 241 requests
FIX
2.8 MB transferred, 241 requests
Warning::
Page weighs 6.6 MB (2.8 MB transferred)
Warning::
JavaScript is 1.2 MB — consider code splitting or lazy loading
Large JavaScript bundles delay interactivity. Split code by route or defer non-critical scripts.
Got: 1.2 MB
Info::
Fonts are 569 KB — consider subsetting or using system fonts
Subset fonts to include only used characters, or switch to system font stacks.
Got: 569 KB
Warning::
241 HTTP requests — consider bundling or reducing
Each request adds latency. Bundle small files, use sprites, or eliminate unnecessary requests.
Info::
Estimated 0.59 g CO2 per page load
2.8 MB / 2.4 MB budget
2.8 MB transferred
241 requests
0.59 g CO2 per page load
JavaScript 1.2 MiB 42%
Images 899.4 KiB 31%
Fonts 569.2 KiB 20%
CSS 128.4 KiB 4%
HTML 66.5 KiB 2%
Other 5.4 KiB 0%
Other 4.2 KiB 0%
Other 2.7 KiB 0%
Other 1.7 KiB 0%
Other 0 B 0%
0 2.4 MB 4.9 MB
Over 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

Subset fonts to include only used characters, or switch to system font stacks.

Why this matters

Font payload is large — subset to used glyphs only, or fall back to system fonts (zero load time).

Source: web.dev font loading

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

F
JS Execution Cost
Action
6931ms total JS execution
FIX
6931ms total JS execution
Warning::
Unattributable: 1555ms CPU time
Warning::
https://www.brevo.com/_next/static/chunks/3526-a2f...: 1140ms CPU time
Warning::
https://www.brevo.com/: 1021ms CPU time
Warning::
https://metrics.brevo.com/dt.js?id=MKMDTST: 756ms CPU time
Warning::
https://assets.brevo.com/js/fingerprint-source.js: 440ms CPU time
Warning::
Third-party scripts: 4221ms (61% of total)

Main Thread Breakdown

Script Evaluation 48% Other 27% Style & Layout 8% Script Parsing & Compilation 7% Parse HTML & CSS 6% Rendering 3%
ScriptTotalScriptingParse/CompileParty
Unattributable1555ms151ms0ms3rd
https://www.brevo.com/_next/static/chunks/3526-a2f2ef44e1290d15.js1140ms669ms16ms1st
https://www.brevo.com/1021ms93ms45ms1st
https://metrics.brevo.com/dt.js?id=MKMDTST756ms624ms79ms3rd
https://assets.brevo.com/js/fingerprint-source.js440ms232ms0ms3rd
https://www.googletagmanager.com/gtag/js?id=G-V8SFL2N220&cx=c&gtm=4e6460434ms372ms57ms3rd
https://analytics.tiktok.com/i18n/pixel/static/main.MWE0ZWQ3ZWQwOQ.js298ms230ms62ms3rd
https://try.abtasty.com/f9a3e011099d4b460c457de53a360bc8/main.79007216ea11a6775b93.js281ms232ms29ms3rd
https://www.brevo.com/_next/static/chunks/fd9d1056-a07975a04e514552.js269ms209ms16ms1st
https://scripts.clarity.ms/0.8.59/clarity.js234ms194ms9ms3rd

Showing top 10 of 14 scripts

D
JS Bundles
Action
49 scripts, 367 KB unused
FIX
49 scripts, 367 KB unused
Warning::
https://www.brevo.com/_next/static/chunks/1954-3ac...: 76 KB unused (67%)
Consider code splitting or tree shaking to reduce unused code.
Warning::
https://www.brevo.com/_next/static/chunks/2183-55f...: 75 KB unused (69%)
Consider code splitting or tree shaking to reduce unused code.
Warning::
https://analytics.tiktok.com/i18n/pixel/static/mai...: 64 KB unused (53%)
Consider code splitting or tree shaking to reduce unused code.
Warning::
https://metrics.brevo.com/dt.js?id=MKMDTST: 61 KB unused (31%)
Consider code splitting or tree shaking to reduce unused code.
Warning::
https://www.googletagmanager.com/gtag/js?id=G-V8SF...: 61 KB unused (34%)
Consider code splitting or tree shaking to reduce unused code.
Info::
Total unused JavaScript: 367 KB
367 KB unused JavaScript

Downloaded but never executed on this page.

ScriptSizeUnusedMinifiedParty
https://www.brevo.com/_next/static/chunks/1954-3acac796a2557f12.js114 KB76 KB (67%)✓1st
https://www.brevo.com/_next/static/chunks/2183-55f69af35b8bbdc9.js109 KB75 KB (69%)✓1st
https://analytics.tiktok.com/i18n/pixel/static/main.MWE0ZWQ3ZWQwOQ.js122 KB64 KB (53%)✓3rd
https://metrics.brevo.com/dt.js?id=MKMDTST196 KB61 KB (31%)✓3rd
https://www.googletagmanager.com/gtag/js?id=G-V8SFL2N220&cx=c&gtm=4e6460178 KB61 KB (34%)✓3rd
https://try.abtasty.com/f9a3e011099d4b460c457de53a360bc8/main.79007216ea11a6775b93.js64 KB31 KB (48%)✓3rd
https://www.brevo.com/_next/static/chunks/9240.05f312642d992554.js0 KB—✓1st
https://snap.licdn.com/li.lms-analytics/insight.min.js19 KB—✓3rd
https://www.brevo.com/_next/static/chunks/967-babf75983dd47872.js33 KB—✓1st
https://www.brevo.com/_next/static/chunks/app/%5Blang%5D/error-0de9c8c44b0c01d6.js5 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

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

B
Third-Party Impact
57% third-party, 0 ms blocking
REVIEW
57% third-party, 0 ms blocking
Warning::
Third-party code accounts for 57% of page weight (1.6 MiB of 2.8 MiB)
Info::
Third-party blocking time is low (0 ms)
43%
57%
First-party Third-party
B
Image Optimization
79 images, 0 KB saveable
REVIEW
79 images, 0 KB saveable
Warning::
https://corp-backend.brevo.com/wp-content/uploads/... is missing width/height — may cause layout shift
Set explicit width and height to prevent CLS.
79 images 899 KB
0 oversized -0 KB
38 legacy format
1 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

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
8 fonts (569 KB)
PASS
8 fonts (569 KB)
Info::
8 font(s) use font-display: swap (FOUT risk but functional)

Web fonts

8

569 KB total

Render-blocking

0

of 8

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 16.0 s 18.0 s 20.0 s FCP 6.0 s LCP 20.7 shttps://www.brevo.com/_next/static/media/28985c33c4eca2d2-s.p.woff228985c33c4eca2d2-s.p.woff2 https://www.brevo.com/_next/static/media/28985c33c4eca2d2-s.p.woff2 — 40.5 KiB — 0 ms — font-display: swaphttps://www.brevo.com/_next/static/media/579e0f95cacfae57-s.p.woff2579e0f95cacfae57-s.p.woff2 https://www.brevo.com/_next/static/media/579e0f95cacfae57-s.p.woff2 — 104.1 KiB — 0 ms — font-display: swaphttps://www.brevo.com/_next/static/media/79a9efa443859920-s.p.woff279a9efa443859920-s.p.woff2 https://www.brevo.com/_next/static/media/79a9efa443859920-s.p.woff2 — 41.1 KiB — 0 ms — font-display: swaphttps://www.brevo.com/_next/static/media/a9949784d907d5c6-s.p.woff2a9949784d907d5c6-s.p.woff2 https://www.brevo.com/_next/static/media/a9949784d907d5c6-s.p.woff2 — 40.6 KiB — 0 ms — font-display: swaphttps://www.brevo.com/_next/static/media/d528b8f1bda496c9-s.p.woff2d528b8f1bda496c9-s.p.woff2 https://www.brevo.com/_next/static/media/d528b8f1bda496c9-s.p.woff2 — 38.3 KiB — 0 ms — font-display: swaphttps://www.brevo.com/_next/static/media/dc792b508e6f91c7-s.p.woff2dc792b508e6f91c7-s.p.woff2 https://www.brevo.com/_next/static/media/dc792b508e6f91c7-s.p.woff2 — 103.9 KiB — 0 ms — font-display: swaphttps://www.brevo.com/_next/static/media/f1f0c35b32161446-s.p.woff2f1f0c35b32161446-s.p.woff2 https://www.brevo.com/_next/static/media/f1f0c35b32161446-s.p.woff2 — 97.0 KiB — 0 ms — font-display: swaphttps://www.brevo.com/_next/static/media/fcb100c7607696fd-s.p.woff2fcb100c7607696fd-s.p.woff2 https://www.brevo.com/_next/static/media/fcb100c7607696fd-s.p.woff2 — 103.8 KiB — 0 ms — font-display: swap
28985c33c4eca2d2-s.p.woff2 woff2 swap
Size 40 KB
Load time 0 ms
Start 0 ms
Risk FOUT — text flashes from fallback to web font
579e0f95cacfae57-s.p.woff2 woff2 swap
Size 104 KB
Load time 0 ms
Start 0 ms
Risk FOUT — text flashes from fallback to web font
  • Subset this font — over 100 KB suggests Latin Extended or full glyph coverage that most pages don't need
79a9efa443859920-s.p.woff2 woff2 swap
Size 41 KB
Load time 0 ms
Start 0 ms
Risk FOUT — text flashes from fallback to web font
a9949784d907d5c6-s.p.woff2 woff2 swap
Size 41 KB
Load time 0 ms
Start 0 ms
Risk FOUT — text flashes from fallback to web font
d528b8f1bda496c9-s.p.woff2 woff2 swap
Size 38 KB
Load time 0 ms
Start 0 ms
Risk FOUT — text flashes from fallback to web font
dc792b508e6f91c7-s.p.woff2 woff2 swap
Size 104 KB
Load time 0 ms
Start 0 ms
Risk FOUT — text flashes from fallback to web font
  • Subset this font — over 100 KB suggests Latin Extended or full glyph coverage that most pages don't need
f1f0c35b32161446-s.p.woff2 woff2 swap
Size 97 KB
Load time 0 ms
Start 0 ms
Risk FOUT — text flashes from fallback to web font
fcb100c7607696fd-s.p.woff2 woff2 swap
Size 104 KB
Load time 0 ms
Start 0 ms
Risk FOUT — text flashes from fallback to web font
  • Subset this font — over 100 KB suggests Latin Extended or full glyph coverage that most pages don't need
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)

Fixing the unchecked items could save ~156 KB and ~312 ms

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
72 hints, 0 missing preconnects
PASS
72 hints, 0 missing preconnects
Info::
Page uses 72 resource hint(s)

Current Resource Hints

preconnect
4
preload
+58
68
dns-prefetch
—
prefetch
—

72 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
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=28800 (8 hours)
PASS
max-age=28800 (8 hours)
Info::
Cache-Control header is set
Got: public, max-age=28800
Info::
Effective TTL: 8 hours (max-age=28800)
Info::
Last-Modified header present
Cache-Control

public, max-age=28800

DirectiveValueMeaning
public—Any cache may store this response
max-age28800Cache for 8 hours
Effective TTL: 28800 seconds
Network Waterfall
241 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
61% of JavaScript execution is third-party
First-party Third-party 4221ms · 611KB · €46/mo
Unattributable
Other
Costly
Execution 1555ms
Transfer 0 KB
Monthly Cost €17/mo
metrics.brevo.com
Other
Costly
Execution 756ms
Transfer 196 KB
Unused 31%
Monthly Cost €8/mo
assets.brevo.com
Other
Costly
Execution 440ms
Transfer 15 KB
Monthly Cost €5/mo
Google Tag Manager
Tag Manager
Costly
Execution 434ms
Transfer 178 KB
Unused 34%
Monthly Cost €5/mo
analytics.tiktok.com
Other
Costly
Execution 298ms
Transfer 122 KB
Unused 53%
Monthly Cost €3/mo
try.abtasty.com
Other
Costly
Execution 281ms
Transfer 64 KB
Unused 48%
Monthly Cost €3/mo
Microsoft Clarity
Session Replay
Costly
Execution 234ms
Transfer 26 KB
Monthly Cost €3/mo
app.planhat.com
Other
Optional
Execution 173ms
Transfer 3 KB
Monthly Cost €2/mo
static.cloudflareinsights.com
Other
Optional
Execution 51ms
Transfer 7 KB
Monthly Cost €1/mo

These scripts may cost more than they're worth

  • Unattributable adds 1555ms and costs ~€17/month
  • metrics.brevo.com adds 756ms and costs ~€8/month
  • assets.brevo.com adds 440ms and costs ~€5/month
  • Google Tag Manager adds 434ms and costs ~€5/month
  • analytics.tiktok.com adds 298ms and costs ~€3/month
  • try.abtasty.com adds 281ms and costs ~€3/month
  • Microsoft Clarity adds 234ms and costs ~€3/month

61% 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 1555ms 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

metrics.brevo.com takes 756ms 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

assets.brevo.com takes 440ms 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 434ms 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

analytics.tiktok.com takes 298ms 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

53% of analytics.tiktok.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

try.abtasty.com takes 281ms 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

Microsoft Clarity takes 234ms 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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