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https://www.mailchimp.com

Performance

· 16 checks — Lighthouse + waterfall + sustainability rolled into one auditable list.
SCORE
76
GRADE
C
FIX
4
REVIEW
2
PASS
8
INFO
2

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

Mobile Desktop
33
Performance Overall performance score (0–100) based on Core Web Vitals and other metrics. 90+ is good.
100
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.
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.

4.09 s

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

16.96 s

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

1.56 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.

8.04 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.

17.06 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
16
8 PASS 2 REVIEW 4 FIX
D
Page Weight Budget
Action
2.1 MB transferred, 144 requests
FIX
2.1 MB transferred, 144 requests
Info::
Page weighs 6.8 MB (2.1 MB transferred)
Warning::
JavaScript is 1.5 MB — consider code splitting or lazy loading
Large JavaScript bundles delay interactivity. Split code by route or defer non-critical scripts.
Got: 1.5 MB
Warning::
144 HTTP requests — consider bundling or reducing
Each request adds latency. Bundle small files, use sprites, or eliminate unnecessary requests.
Info::
Estimated 0.45 g CO2 per page load
2.1 MB / 2.4 MB budget
2.1 MB transferred
144 requests
0.45 g CO2 per page load
JavaScript 1.5 MiB 68%
Images 249.8 KiB 11%
Fonts 178.8 KiB 8%
CSS 95.8 KiB 4%
Other 79.6 KiB 4%
HTML 77.4 KiB 4%
Other 10.7 KiB 0%
Other 5.1 KiB 0%
Other 224 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

D
Third-Party Impact
Action
100% third-party, 0 ms blocking
FIX
100% third-party, 0 ms blocking
Warning::
Third-party code accounts for 100% of page weight (2.1 MiB of 2.1 MiB)
Info::
Third-party blocking time is low (0 ms)
100%
First-party Third-party
F
JS Execution Cost
Action
7196ms total JS execution
FIX
7196ms total JS execution
Warning::
https://mailchimp.com/es/: 1254ms CPU time
Warning::
Unattributable: 1049ms CPU time
Warning::
https://mailchimp.com/SVNV/JPUm/9J/NG64/cyzQ/5kitc...: 1049ms CPU time
Warning::
https://mailchimp.com/release/plums/cxp/js/index.5...: 828ms CPU time
Warning::
https://s2.go-mpulse.net/boomerang/QAT5G-9HZLF-7ED...: 459ms CPU time
Warning::
Third-party scripts: 7196ms (100% of total)

Main Thread Breakdown

Script Evaluation 53% Other 21% Style & Layout 8% Script Parsing & Compilation 8% Rendering 6%
ScriptTotalScriptingParse/CompileParty
https://mailchimp.com/es/1254ms25ms16ms3rd
Unattributable1049ms74ms0ms3rd
https://mailchimp.com/SVNV/JPUm/9J/NG64/cyzQ/5kitcDbzVkhSQkap/Ay4KP0QVAw/ex9XBDBX/LEwB1049ms818ms48ms3rd
https://mailchimp.com/release/plums/cxp/js/index.570b2f64.1.js828ms710ms28ms3rd
https://s2.go-mpulse.net/boomerang/QAT5G-9HZLF-7EDMX-YMVCJ-QZJDA459ms115ms85ms3rd
https://mailchimp.com/release/plums/chunks/js/2362.49d5f9e21a4f8705.1.js357ms286ms1ms3rd
https://mailchimp.com/metrics/gtd?id=G-N5HD1RTH6E&cx=c&gtm=4e6460332ms240ms75ms3rd
https://mailchimp.com/metrics/?id=GTM-59GS5R2&gtm=4e6460331ms216ms87ms3rd
https://mailchimp.com/metrics/?id=265ms185ms77ms3rd
https://plugin.intuitcdn.net/web-shell/5.60.1/integration/adk-api.js251ms239ms1ms3rd

Showing top 10 of 20 scripts

F
JS Bundles
Action
91 scripts, 503 KB unused
FIX
91 scripts, 503 KB unused
Warning::
https://mailchimp.com/metrics/?id=: 80 KB unused (36%)
Consider code splitting or tree shaking to reduce unused code.
Warning::
https://mailchimp.com/metrics/gtd?id=G-N5HD1RTH6E&...: 78 KB unused (43%)
Consider code splitting or tree shaking to reduce unused code.
Warning::
https://accounts.google.com/gsi/client: 77 KB unused (83%)
Consider code splitting or tree shaking to reduce unused code.
Warning::
https://mailchimp.com/metrics/?id=GTM-59GS5R2&gtm=...: 72 KB unused (53%)
Consider code splitting or tree shaking to reduce unused code.
Warning::
https://mailchimp.com/metrics/?id=GTM-5XRCGV8&gtm=...: 71 KB unused (53%)
Consider code splitting or tree shaking to reduce unused code.
Info::
Total unused JavaScript: 503 KB
503 KB unused JavaScript

Downloaded but never executed on this page.

ScriptSizeUnusedMinifiedParty
https://mailchimp.com/metrics/?id=221 KB80 KB (36%)✓3rd
https://mailchimp.com/metrics/gtd?id=G-N5HD1RTH6E&cx=c&gtm=4e6460182 KB78 KB (43%)✓3rd
https://accounts.google.com/gsi/client93 KB77 KB (83%)✓3rd
https://mailchimp.com/metrics/?id=GTM-59GS5R2&gtm=4e6460136 KB72 KB (53%)✓3rd
https://mailchimp.com/metrics/?id=GTM-5XRCGV8&gtm=4e6460135 KB71 KB (53%)✓3rd
https://mailchimp.com/SVNV/JPUm/9J/NG64/cyzQ/5kitcDbzVkhSQkap/Ay4KP0QVAw/ex9XBDBX/LEwB173 KB37 KB (22%)✓3rd
https://plugin.intuitcdn.net/web-shell/5.60.1/integration/3935.js40 KB33 KB (85%)✓3rd
https://mailchimp.com/release/plums/cxp/js/index.570b2f64.1.js60 KB29 KB (49%)✓3rd
https://s2.go-mpulse.net/boomerang/QAT5G-9HZLF-7EDMX-YMVCJ-QZJDA58 KB24 KB (41%)✓3rd
https://mailchimp.com/release/plums/chunks/js/4073.0cd157ccb57023d8.1.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

B
Image Optimization
19 images, 0 KB saveable
REVIEW
19 images, 0 KB saveable
Info::
All images are well-optimized
19 images 250 KB
0 oversized -0 KB
6 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

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
5 fonts (179 KB)
PASS
5 fonts (179 KB)
Info::
5 font(s) use font-display: swap (FOUT risk but functional)

Web fonts

5

179 KB total

Render-blocking

0

of 5

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 FCP 4.1 s LCP 17.0 shttps://mailchimp.com/release/plums/659baf8b2573503b.woff2659baf8b2573503b.woff2 https://mailchimp.com/release/plums/659baf8b2573503b.woff2 — 32.2 KiB — 0 ms — font-display: swaphttps://mailchimp.com/release/plums/ea9371020395bcec.woff2ea9371020395bcec.woff2 https://mailchimp.com/release/plums/ea9371020395bcec.woff2 — 34.5 KiB — 0 ms — font-display: swaphttps://mailchimp.com/release/plums/b4358c1049ee69f4.woff2b4358c1049ee69f4.woff2 https://mailchimp.com/release/plums/b4358c1049ee69f4.woff2 — 36.3 KiB — 0 ms — font-display: swaphttps://mailchimp.com/release/plums/c477e5e371f1219d.woff2c477e5e371f1219d.woff2 https://mailchimp.com/release/plums/c477e5e371f1219d.woff2 — 35.2 KiB — 0 ms — font-display: swaphttps://mailchimp.com/release/plums/f503b10a8b819ad9.woff2f503b10a8b819ad9.woff2 https://mailchimp.com/release/plums/f503b10a8b819ad9.woff2 — 40.6 KiB — 0 ms — font-display: swap
659baf8b2573503b.woff2 woff2 swap
Size 32 KB
Load time 0 ms
Start 0 ms
Risk FOUT — text flashes from fallback to web font
ea9371020395bcec.woff2 woff2 swap
Size 34 KB
Load time 0 ms
Start 0 ms
Risk FOUT — text flashes from fallback to web font
b4358c1049ee69f4.woff2 woff2 swap
Size 36 KB
Load time 0 ms
Start 0 ms
Risk FOUT — text flashes from fallback to web font
c477e5e371f1219d.woff2 woff2 swap
Size 35 KB
Load time 0 ms
Start 0 ms
Risk FOUT — text flashes from fallback to web font
f503b10a8b819ad9.woff2 woff2 swap
Size 41 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
15 hints, 0 missing preconnects
PASS
15 hints, 0 missing preconnects
Info::
Page uses 15 resource hint(s)

Current Resource Hints

preconnect
3
preload
+2
12
dns-prefetch
—
prefetch
—

15 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
HTTP Caching
max-age=60 (1 minute)
PASS
max-age=60 (1 minute)
Info::
Cache-Control header is set
Got: max-age=60
Info::
Effective TTL: 1 minute (max-age=60)
Info::
No ETag or Last-Modified header
Conditional requests (304 Not Modified) are not possible without validators.
Cache-Control

max-age=60

DirectiveValueMeaning
max-age60Cache for 1 minute
Effective TTL: 60 seconds
Network Waterfall
144 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
100% of JavaScript execution is third-party
First-party Third-party 7196ms · 980KB · $41/mo
mailchimp.com
Other
Costly
Execution 1254ms
Transfer 77 KB
Monthly Cost $7/mo
Unattributable
Other
Costly
Execution 1049ms
Transfer 0 KB
Monthly Cost $6/mo
mailchimp.com
Other
Costly
Execution 1049ms
Transfer 1 KB
Unused 22%
Monthly Cost $6/mo
mailchimp.com
Other
Costly
Execution 828ms
Transfer 60 KB
Unused 49%
Monthly Cost $5/mo
s2.go-mpulse.net
Other
Costly
Execution 459ms
Transfer 58 KB
Unused 41%
Monthly Cost $3/mo
mailchimp.com
Other
Costly
Execution 357ms
Transfer 3 KB
Monthly Cost $2/mo
mailchimp.com
Other
Costly
Execution 332ms
Transfer 182 KB
Unused 43%
Monthly Cost $2/mo
mailchimp.com
Other
Costly
Execution 331ms
Transfer 136 KB
Unused 53%
Monthly Cost $2/mo
mailchimp.com
Other
Costly
Execution 265ms
Transfer 221 KB
Unused 36%
Monthly Cost $2/mo
plugin.intuitcdn.net
Other
Costly
Execution 251ms
Transfer 3 KB
Monthly Cost $1/mo
mailchimp.com
Other
Costly
Execution 246ms
Transfer 2 KB
Monthly Cost $1/mo
mailchimp.com
Other
Costly
Execution 205ms
Transfer 135 KB
Unused 53%
Monthly Cost $1/mo
plugin.intuitcdn.net
Other
Optional
Execution 104ms
Transfer 6 KB
Monthly Cost $1/mo
unpkg
CDN
Optional
Execution 83ms
Transfer 5 KB
Monthly Cost $0/mo
mailchimp.com
Other
Optional
Execution 73ms
Transfer 27 KB
Monthly Cost $0/mo
plugin.intuitcdn.net
Other
Optional
Execution 69ms
Transfer 4 KB
Monthly Cost $0/mo
plugin.intuitcdn.net
Other
Optional
Execution 68ms
Transfer 14 KB
Monthly Cost $0/mo
plugin.intuitcdn.net
Other
Optional
Execution 63ms
Transfer 2 KB
Monthly Cost $0/mo
mailchimp.com
Other
Optional
Execution 58ms
Transfer 38 KB
Monthly Cost $0/mo
plugin.intuitcdn.net
Other
Optional
Execution 50ms
Transfer 4 KB
Monthly Cost $0/mo

These scripts may cost more than they're worth

  • mailchimp.com adds 1254ms and costs ~$7/month
  • Unattributable adds 1049ms and costs ~$6/month
  • mailchimp.com adds 1049ms and costs ~$6/month
  • mailchimp.com adds 828ms and costs ~$5/month
  • s2.go-mpulse.net adds 459ms and costs ~$3/month
  • mailchimp.com adds 357ms and costs ~$2/month
  • mailchimp.com adds 332ms and costs ~$2/month
  • mailchimp.com adds 331ms and costs ~$2/month
  • mailchimp.com adds 265ms and costs ~$2/month
  • plugin.intuitcdn.net adds 251ms and costs ~$1/month
  • mailchimp.com adds 246ms and costs ~$1/month
  • mailchimp.com adds 205ms and costs ~$1/month

100% of JavaScript execution time is spent on third-party scripts. Consider auditing which scripts are essential.

Why this matters

When third-party JS execution time exceeds your own, performance gains from frontend work are capped by code you don't own.

Learn more ▾

Every millisecond of third-party JS competes with your own for main-thread time. If their share is bigger than yours, optimization on your code base barely moves the needle. Audit, defer, or remove third-parties before further frontend optimization. Use Lighthouse's third-party audit to identify the worst offenders.

Source: web.dev

mailchimp.com takes 1254ms 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 1049ms 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

mailchimp.com takes 1049ms 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

mailchimp.com takes 828ms 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

s2.go-mpulse.net takes 459ms 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

mailchimp.com takes 357ms 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

mailchimp.com takes 332ms 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

mailchimp.com takes 331ms 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 mailchimp.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

mailchimp.com takes 265ms 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

plugin.intuitcdn.net takes 251ms 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

mailchimp.com takes 246ms 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

mailchimp.com takes 205ms 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 mailchimp.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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