Browsers will use heuristic caching, which can be unpredictable. Set explicit cache headers.
No Cache-Control header
Adding a Cache-Control header can significantly improve repeat-visit performance.
B
Image Optimization
19 images, 0 KB saveable
REVIEW
19 images, 0 KB saveable
Info::
✓
All images are well-optimized
19images684 KB
0oversized-0 KB
16legacy format
0missing dimensionsCLS 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::
i
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
TransferFOIT (block)FOUT (swap)
374b3182e5e57bcb-s.p.woff2woff2swap
Size34 KB
Load time20 ms
Start365 ms
RiskFOUT — text flashes from fallback to web font
font-woff;base64,d09GRg...woffswap
Size63 KB
Load time67 ms
Start450 ms
RiskFOUT — text flashes from fallback to web font
Convert to woff2 for ~30% smaller file size
font-woff;base64,d09GRg...woffswap
Size63 KB
Load time64 ms
Start458 ms
RiskFOUT — text flashes from fallback to web font
Convert to woff2 for ~30% smaller file size
font-woff;base64,d09GRg...woffswap
Size48 KB
Load time65 ms
Start459 ms
RiskFOUT — 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+
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
71 requests over 1982ms
INFO
HTML JavaScript CSS Images Fonts XHR/Fetch Other
Third-Party Script Cost
Per-script blocking time, transfer cost, and cache headers
INFO
100%of JavaScript execution is third-party
First-party Third-party5773ms · 1815KB · £60/mo
Script
Category
Execution
Transfer
Unused
Monthly Cost
Verdict
www.eventbrite.co.uk
www.eventbrite.co.uk
Other
1156ms
42 KB
—
£12/mo
Costly
www.eventbrite.co.uk
www.eventbrite.co.uk
Other
826ms
28 KB
—
£9/mo
Costly
Unattributable
Unattributable
Other
596ms
0 KB
—
£6/mo
Costly
Google Tag Manager
www.googletagmanager.com
Tag Manager
532ms
160 KB
42%
£6/mo
Costly
Google Tag Manager
www.googletagmanager.com
Tag Manager
507ms
197 KB
35%
£5/mo
Costly
www.eventbrite.co.uk
www.eventbrite.co.uk
Other
335ms
206 KB
54%
£3/mo
Costly
Google Tag Manager
www.googletagmanager.com
Tag Manager
250ms
131 KB
47%
£3/mo
Costly
www.eventbrite.co.uk
www.eventbrite.co.uk
Other
218ms
1 KB
—
£2/mo
Costly
Google Tag Manager
www.googletagmanager.com
Tag Manager
203ms
145 KB
45%
£2/mo
Costly
cdntranscend.eventbrite.com
cdntranscend.eventbrite.com
Other
192ms
90 KB
42%
£2/mo
Optional
www.eventbrite.co.uk
www.eventbrite.co.uk
Other
181ms
42 KB
—
£2/mo
Optional
Google Tag Manager
www.googletagmanager.com
Tag Manager
173ms
147 KB
44%
£2/mo
Optional
Google Tag Manager
www.googletagmanager.com
Tag Manager
151ms
146 KB
44%
£2/mo
Optional
Google Tag Manager
www.googletagmanager.com
Tag Manager
136ms
145 KB
44%
£1/mo
Optional
cdntranscend.eventbrite.com
cdntranscend.eventbrite.com
Other
132ms
69 KB
—
£1/mo
Optional
www.eventbrite.co.uk
www.eventbrite.co.uk
Other
74ms
204 KB
32%
£1/mo
Optional
www.eventbrite.co.uk
www.eventbrite.co.uk
Other
57ms
30 KB
—
£1/mo
Optional
www.eventbrite.co.uk
www.eventbrite.co.uk
Other
55ms
31 KB
66%
£1/mo
Optional
www.eventbrite.co.uk
Other
Costly
Execution1156ms
Transfer42 KB
Monthly Cost£12/mo
www.eventbrite.co.uk
Other
Costly
Execution826ms
Transfer28 KB
Monthly Cost£9/mo
Unattributable
Other
Costly
Execution596ms
Transfer0 KB
Monthly Cost£6/mo
Google Tag Manager
Tag Manager
Costly
Execution532ms
Transfer160 KB
Unused42%
Monthly Cost£6/mo
Google Tag Manager
Tag Manager
Costly
Execution507ms
Transfer197 KB
Unused35%
Monthly Cost£5/mo
www.eventbrite.co.uk
Other
Costly
Execution335ms
Transfer206 KB
Unused54%
Monthly Cost£3/mo
Google Tag Manager
Tag Manager
Costly
Execution250ms
Transfer131 KB
Unused47%
Monthly Cost£3/mo
www.eventbrite.co.uk
Other
Costly
Execution218ms
Transfer1 KB
Monthly Cost£2/mo
Google Tag Manager
Tag Manager
Costly
Execution203ms
Transfer145 KB
Unused45%
Monthly Cost£2/mo
cdntranscend.eventbrite.com
Other
Optional
Execution192ms
Transfer90 KB
Unused42%
Monthly Cost£2/mo
www.eventbrite.co.uk
Other
Optional
Execution181ms
Transfer42 KB
Monthly Cost£2/mo
Google Tag Manager
Tag Manager
Optional
Execution173ms
Transfer147 KB
Unused44%
Monthly Cost£2/mo
Google Tag Manager
Tag Manager
Optional
Execution151ms
Transfer146 KB
Unused44%
Monthly Cost£2/mo
Google Tag Manager
Tag Manager
Optional
Execution136ms
Transfer145 KB
Unused44%
Monthly Cost£1/mo
cdntranscend.eventbrite.com
Other
Optional
Execution132ms
Transfer69 KB
Monthly Cost£1/mo
www.eventbrite.co.uk
Other
Optional
Execution74ms
Transfer204 KB
Unused32%
Monthly Cost£1/mo
www.eventbrite.co.uk
Other
Optional
Execution57ms
Transfer30 KB
Monthly Cost£1/mo
www.eventbrite.co.uk
Other
Optional
Execution55ms
Transfer31 KB
Unused66%
Monthly Cost£1/mo
These scripts may cost more than they're worth
www.eventbrite.co.uk adds 1156ms and costs ~£12/month
www.eventbrite.co.uk adds 826ms and costs ~£9/month
Unattributable adds 596ms and costs ~£6/month
Google Tag Manager adds 532ms and costs ~£6/month
Google Tag Manager adds 507ms and costs ~£5/month
www.eventbrite.co.uk adds 335ms and costs ~£3/month
Google Tag Manager adds 250ms and costs ~£3/month
www.eventbrite.co.uk adds 218ms and costs ~£2/month
Google Tag Manager adds 203ms and costs ~£2/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
www.eventbrite.co.uk takes 1156ms 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
www.eventbrite.co.uk takes 826ms 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 596ms 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 532ms 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 507ms 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
www.eventbrite.co.uk takes 335ms 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 www.eventbrite.co.uk'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 250ms 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
www.eventbrite.co.uk takes 218ms 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 203ms 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
66% of www.eventbrite.co.uk'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.