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
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 (48 KB)
PASS
1 fonts (48 KB)
Info::
i
1 font(s) use font-display: swap (FOUT risk but functional)
Web fonts
1
48 KB total
Render-blocking
0
of 1
Dominant font-display
swap
Most common across fonts
Font loading timeline
TransferFOIT (block)FOUT (swap)
NexusSansWebPro.c20f87e...woffswap
Size48 KB
Load time41 ms
Start897 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 ~14 KB and ~28 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
No optimization needed
PASS
No optimization needed
Info::
✓
No resource hint issues
Network Waterfall
51 requests over 1839ms
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-party760ms · 524KB · $10/mo
Script
Category
Execution
Transfer
Unused
Monthly Cost
Verdict
Unattributable
Unattributable
Other
294ms
0 KB
—
$4/mo
Costly
www.mendeley.com
www.mendeley.com
Other
269ms
6 KB
—
$4/mo
Costly
assets.adobedtm.com
assets.adobedtm.com
Other
71ms
107 KB
48%
$1/mo
Optional
OneTrust
cdn.cookielaw.org
Consent
67ms
119 KB
52%
$1/mo
Essential
static.mendeley.com
static.mendeley.com
Other
59ms
292 KB
7%
$1/mo
Optional
Unattributable
Other
Costly
Execution294ms
Transfer0 KB
Monthly Cost$4/mo
www.mendeley.com
Other
Costly
Execution269ms
Transfer6 KB
Monthly Cost$4/mo
assets.adobedtm.com
Other
Optional
Execution71ms
Transfer107 KB
Unused48%
Monthly Cost$1/mo
OneTrust
Consent
Essential
Execution67ms
Transfer119 KB
Unused52%
Monthly Cost$1/mo
static.mendeley.com
Other
Optional
Execution59ms
Transfer292 KB
Unused7%
Monthly Cost$1/mo
These scripts may cost more than they're worth
Unattributable adds 294ms and costs ~$4/month
www.mendeley.com adds 269ms and costs ~$4/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
Unattributable takes 294ms 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.mendeley.com takes 269ms 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
52% of OneTrust'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.