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https://www.eventbrite.com

Performance

· 14 checks — Lighthouse + waterfall + sustainability rolled into one auditable list.
SCORE
66
GRADE
D
FIX
4
REVIEW
2
PASS
6
INFO
2

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

Mobile Desktop
31
Performance Overall performance score (0–100) based on Core Web Vitals and other metrics. 90+ is good.
95
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.

3.51 s

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

14.57 s

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

5.09 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.

7.68 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.

32.05 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
6 PASS 2 REVIEW 4 FIX
F
Page Weight Budget
Action
4.2 MB transferred, 155 requests
FIX
4.2 MB transferred, 155 requests
Critical::
Page weighs 11.5 MB (4.2 MB transferred)
Warning::
JavaScript is 2.8 MB — consider code splitting or lazy loading
Large JavaScript bundles delay interactivity. Split code by route or defer non-critical scripts.
Got: 2.8 MB
Info::
CSS is 319 KB — consider purging unused styles
Remove unused CSS rules with tools like PurgeCSS to reduce stylesheet size.
Got: 319 KB
Info::
Fonts are 209 KB — consider subsetting or using system fonts
Subset fonts to include only used characters, or switch to system font stacks.
Got: 209 KB
Warning::
155 HTTP requests — consider bundling or reducing
Each request adds latency. Bundle small files, use sprites, or eliminate unnecessary requests.
Info::
Estimated 0.89 g CO2 per page load
4.2 MB / 2.4 MB budget
4.2 MB transferred
155 requests
0.89 g CO2 per page load
JavaScript 2.8 MiB 67%
Images 638.4 KiB 15%
CSS 318.7 KiB 7%
Fonts 208.8 KiB 5%
Other 174.7 KiB 4%
Other 50.4 KiB 1%
HTML 28.7 KiB 1%
Other 4.1 KiB 0%
Other 4.1 KiB 0%
Other 1.9 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

Remove unused CSS rules with tools like PurgeCSS to reduce stylesheet size.

Why this matters

CSS bundle is large — purge unused styles (PurgeCSS, Tailwind JIT) to reduce CSS payload.

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

D
Third-Party Impact
Action
73% third-party, 0 ms blocking
FIX
73% third-party, 0 ms blocking
Warning::
Third-party code accounts for 73% of page weight (3.1 MiB of 4.2 MiB)
Info::
Third-party blocking time is low (0 ms)
27%
73%
First-party Third-party
F
JS Execution Cost
Action
13334ms total JS execution
FIX
13334ms total JS execution
Warning::
https://www.eventbrite.com/home/_next/static/chunk...: 1628ms CPU time
Warning::
Unattributable: 1539ms CPU time
Warning::
https://www.eventbrite.com/: 1263ms CPU time
Warning::
https://t.contentsquare.net/uxa/757e6910546e7.js: 1104ms CPU time
Warning::
https://js.hs-analytics.net/analytics/177532680000...: 884ms CPU time
Warning::
Third-party scripts: 8944ms (67% of total)

Main Thread Breakdown

Script Evaluation 66% Other 13% Style & Layout 8% Script Parsing & Compilation 8%
ScriptTotalScriptingParse/CompileParty
https://www.eventbrite.com/home/_next/static/chunks/framework-945b357d4a851f4b.js1628ms1393ms22ms1st
Unattributable1539ms215ms0ms3rd
https://www.eventbrite.com/1263ms14ms1ms1st
https://t.contentsquare.net/uxa/757e6910546e7.js1104ms1001ms56ms3rd
https://js.hs-analytics.net/analytics/1775326800000/8020908.js884ms617ms11ms3rd
https://www.googletagmanager.com/gtm.js?id=GTM-5P8FXJ710ms598ms79ms3rd
https://www.googletagmanager.com/gtag/js?id=AW-1071787441&cx=c&gtm=4e6411606ms542ms58ms3rd
https://www.eventbrite.com/home/_next/static/chunks/pages/_app-58f20aaeb5cf3bf9.js472ms387ms79ms1st
https://www.googletagmanager.com/gtag/js?id=G-TQVES5V6SH&cx=c&gtm=4e6411429ms345ms78ms3rd
https://www.eventbrite.com/home/_next/static/chunks/613.51b8f752b880b047.js400ms243ms22ms1st

Showing top 10 of 32 scripts

F
JS Bundles
Action
60 scripts, 1.1 MB unused
FIX
60 scripts, 1.1 MB unused
Warning::
https://www.eventbrite.com/home/_next/static/chunk...: 130 KB unused (100%)
Consider code splitting or tree shaking to reduce unused code.
Warning::
https://www.eventbrite.com/home/_next/static/chunk...: 109 KB unused (54%)
Consider code splitting or tree shaking to reduce unused code.
Warning::
https://www.googletagmanager.com/gtag/js?id=AW-107...: 105 KB unused (73%)
Consider code splitting or tree shaking to reduce unused code.
Warning::
https://t.contentsquare.net/uxa/757e6910546e7.js: 79 KB unused (49%)
Consider code splitting or tree shaking to reduce unused code.
Warning::
https://www.googletagmanager.com/gtag/js?id=G-TQVE...: 66 KB unused (42%)
Consider code splitting or tree shaking to reduce unused code.
Info::
Total unused JavaScript: 1.1 MB
1080 KB unused JavaScript

Downloaded but never executed on this page.

ScriptSizeUnusedMinifiedParty
https://www.eventbrite.com/home/_next/static/chunks/3b999911-e0f67891397df603.js130 KB130 KB (100%)✓1st
https://www.eventbrite.com/home/_next/static/chunks/pages/_app-58f20aaeb5cf3bf9.js204 KB109 KB (54%)✓1st
https://www.googletagmanager.com/gtag/js?id=AW-1071787441144 KB105 KB (73%)✓3rd
https://t.contentsquare.net/uxa/757e6910546e7.js161 KB79 KB (49%)✓3rd
https://www.googletagmanager.com/gtag/js?id=G-TQVES5V6SH&cx=c&gtm=4e6411159 KB66 KB (42%)✓3rd
https://www.googletagmanager.com/gtm.js?id=GTM-5P8FXJ194 KB66 KB (34%)✓3rd
https://www.eventbrite.com/home/_next/static/chunks/5631-74ddad1e2f1aec2d.js186 KB61 KB (33%)✓1st
https://www.googletagmanager.com/gtag/js?id=DC-4080218&cx=c&gtm=4e6411130 KB58 KB (45%)✓3rd
https://analytics.tiktok.com/i18n/pixel/static/main.MWE0ZWQ3ZWQwMQ.js110 KB56 KB (51%)✓3rd
https://www.googletagmanager.com/gtag/js?id=AW-1012298015&cx=c&gtm=4e6411145 KB55 KB (38%)✓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
37 images, 0 KB saveable
REVIEW
37 images, 0 KB saveable
Info::
All images are well-optimized
37 images 638 KB
0 oversized -0 KB
34 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
4 fonts (209 KB)
PASS
4 fonts (209 KB)
Info::
4 font(s) use font-display: swap (FOUT risk but functional)

Web fonts

4

209 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 2.0 s 4.0 s 6.0 s 8.0 s 10.0 s 12.0 s 14.0 s FCP 3.5 s LCP 14.6 shttps://www.eventbrite.com/home/_next/static/media/374b3182e5e57bcb-s.p.woff2374b3182e5e57bcb-s.p.woff2 https://www.eventbrite.com/home/_next/static/media/374b3182e5e57bcb-s.p.woff2 — 34.3 KiB — 0 ms — font-display: swapdata:application/font-woff;base64,d09GRgABAAAAAPvQABIAAAACEEQAAQAyAAAAAAAAAAAAAAAAAAAAAAAAAABGRlRNA…font-woff;base64,d09GRg... data:application/font-woff;base64,d09GRgABAAAAAPvQABIAAAACEEQAAQAyAAAAAAAAAAAAAAAAAAAAAAAAAABGRlRNA… — 63.0 KiB — 0 ms — font-display: swapdata:application/font-woff;base64,d09GRgABAAAAAPyMABIAAAACEGgAAQAyAAAAAAAAAAAAAAAAAAAAAAAAAABGRlRNA…font-woff;base64,d09GRg... data:application/font-woff;base64,d09GRgABAAAAAPyMABIAAAACEGgAAQAyAAAAAAAAAAAAAAAAAAAAAAAAAABGRlRNA… — 63.1 KiB — 0 ms — font-display: swapdata:application/font-woff;base64,d09GRgABAAAAAMHYABIAAAABibwAAQAyAAAAAAAAAAAAAAAAAAAAAAAAAABGRlRNA…font-woff;base64,d09GRg... data:application/font-woff;base64,d09GRgABAAAAAMHYABIAAAABibwAAQAyAAAAAAAAAAAAAAAAAAAAAAAAAABGRlRNA… — 48.5 KiB — 0 ms — font-display: swap
374b3182e5e57bcb-s.p.woff2 woff2 swap
Size 34 KB
Load time 0 ms
Start 0 ms
Risk FOUT — text flashes from fallback to web font
font-woff;base64,d09GRg... woff swap
Size 63 KB
Load time 0 ms
Start 0 ms
Risk FOUT — text flashes from fallback to web font
  • Convert to woff2 for ~30% smaller file size
font-woff;base64,d09GRg... woff swap
Size 63 KB
Load time 0 ms
Start 0 ms
Risk FOUT — text flashes from fallback to web font
  • Convert to woff2 for ~30% smaller file size
font-woff;base64,d09GRg... woff swap
Size 48 KB
Load time 0 ms
Start 0 ms
Risk FOUT — text flashes from fallback to web font
  • Convert to woff2 for ~30% smaller file size
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 ~52 KB and ~104 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
14 hints, 0 missing preconnects
PASS
14 hints, 0 missing preconnects
Info::
Page uses 14 resource hint(s)

Current Resource Hints

preconnect
5
preload
4
dns-prefetch
5
prefetch
—

14 resource hints configured

A+
HTTP Caching
max-age=300 (5 minutes)
PASS
max-age=300 (5 minutes)
Info::
Cache-Control header is set
Got: max-age=300, s-maxage=600, stale-while-revalidate=3600, stale-if-error=86400
Info::
Effective TTL: 5 minutes (max-age=300)
Info::
CDN TTL: 10 minutes (s-maxage=600)
Info::
ETag present — enables conditional (304) responses
Cache-Control

max-age=300, s-maxage=600, stale-while-revalidate=3600, stale-if-error=86400

DirectiveValueMeaning
max-age300Cache for 5 minutes
s-maxage600CDN caches for 10 minutes
stale-while-revalidate3600Serve stale for 1 hour while fetching fresh
stale-if-error86400
Effective TTL: 300 seconds
Network Waterfall
155 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 8944ms · 2034KB · $119/mo
Unattributable
Other
Costly
Execution 1539ms
Transfer 0 KB
Monthly Cost $20/mo
t.contentsquare.net
Other
Costly
Execution 1104ms
Transfer 161 KB
Unused 49%
Monthly Cost $15/mo
HubSpot Analytics
Analytics
Costly
Execution 884ms
Transfer 43 KB
Monthly Cost $12/mo
Google Tag Manager
Tag Manager
Costly
Execution 710ms
Transfer 194 KB
Unused 34%
Monthly Cost $9/mo
Google Tag Manager
Tag Manager
Costly
Execution 606ms
Transfer 143 KB
Unused 38%
Monthly Cost $8/mo
Google Tag Manager
Tag Manager
Costly
Execution 429ms
Transfer 159 KB
Unused 42%
Monthly Cost $6/mo
Google Tag Manager
Tag Manager
Costly
Execution 359ms
Transfer 145 KB
Unused 38%
Monthly Cost $5/mo
Google Tag Manager
Tag Manager
Costly
Execution 354ms
Transfer 145 KB
Unused 38%
Monthly Cost $5/mo
js.hs-banner.com
Other
Costly
Execution 353ms
Transfer 21 KB
Monthly Cost $5/mo
Google Tag Manager
Tag Manager
Costly
Execution 342ms
Transfer 143 KB
Unused 38%
Monthly Cost $5/mo
analytics.tiktok.com
Other
Costly
Execution 316ms
Transfer 110 KB
Unused 51%
Monthly Cost $4/mo
cdntranscend.eventbrite.com
Other
Costly
Execution 274ms
Transfer 91 KB
Unused 50%
Monthly Cost $4/mo
Google Tag Manager
Tag Manager
Costly
Execution 259ms
Transfer 130 KB
Unused 45%
Monthly Cost $3/mo
Heap Analytics
Analytics
Costly
Execution 243ms
Transfer 40 KB
Monthly Cost $3/mo
Facebook Pixel
Advertising
Costly
Execution 237ms
Transfer 95 KB
Unused 35%
Monthly Cost $3/mo
Facebook Pixel
Advertising
Optional
Execution 151ms
Transfer 43 KB
Monthly Cost $2/mo
cdntranscend.eventbrite.com
Other
Optional
Execution 128ms
Transfer 69 KB
Monthly Cost $2/mo
s.pinimg.com
Other
Optional
Execution 127ms
Transfer 27 KB
Monthly Cost $2/mo
js.hubspot.com
Other
Optional
Execution 119ms
Transfer 28 KB
Monthly Cost $2/mo
utt.impactcdn.com
Other
Optional
Execution 102ms
Transfer 21 KB
Monthly Cost $1/mo
Google Tag Manager
Tag Manager
Optional
Execution 95ms
Transfer 144 KB
Unused 73%
Monthly Cost $1/mo
js.usemessages.com
Other
Optional
Execution 95ms
Transfer 33 KB
Monthly Cost $1/mo
analytics.tiktok.com
Other
Optional
Execution 62ms
Transfer 40 KB
Monthly Cost $1/mo
pixel.byspotify.com
Other
Optional
Execution 55ms
Transfer 10 KB
Monthly Cost $1/mo

These scripts may cost more than they're worth

  • Unattributable adds 1539ms and costs ~$20/month
  • t.contentsquare.net adds 1104ms and costs ~$15/month
  • HubSpot Analytics adds 884ms and costs ~$12/month
  • Google Tag Manager adds 710ms and costs ~$9/month
  • Google Tag Manager adds 606ms and costs ~$8/month
  • Google Tag Manager adds 429ms and costs ~$6/month
  • Google Tag Manager adds 359ms and costs ~$5/month
  • Google Tag Manager adds 354ms and costs ~$5/month
  • js.hs-banner.com adds 353ms and costs ~$5/month
  • Google Tag Manager adds 342ms and costs ~$5/month
  • analytics.tiktok.com adds 316ms and costs ~$4/month
  • cdntranscend.eventbrite.com adds 274ms and costs ~$4/month
  • Google Tag Manager adds 259ms and costs ~$3/month
  • Heap Analytics adds 243ms and costs ~$3/month
  • Facebook Pixel adds 237ms and costs ~$3/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 1539ms 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

t.contentsquare.net takes 1104ms 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

HubSpot Analytics takes 884ms 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 710ms 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 606ms 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 429ms 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 359ms 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 354ms 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

js.hs-banner.com takes 353ms 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 342ms 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 316ms 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

51% 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

cdntranscend.eventbrite.com takes 274ms 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

50% of cdntranscend.eventbrite.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 259ms 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

Heap Analytics takes 243ms 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

Facebook Pixel takes 237ms 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

73% of Google Tag Manager'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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