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
12 images, 0 KB saveable
REVIEW
12 images, 0 KB saveable
Warning::
!
https://www.marinetraffic.com/img/LogoDesktop@2x.p... is missing width/height — may cause layout shift
Set explicit width and height to prevent CLS.
12images387 KB
0oversized-0 KB
10legacy format
1missing dimensionsCLS 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
9 fonts (117 KB)
PASS
9 fonts (117 KB)
Info::
i
9 font(s) use font-display: swap (FOUT risk but functional)
Web fonts
9
117 KB total
Render-blocking
0
of 9
Dominant font-display
swap
Most common across fonts
Font loading timeline
TransferFOIT (block)FOUT (swap)
KFO7CnqEu92Fr1ME7kSn66a...woff2swap
Size37 KB
Load time9 ms
Start1.2 s
RiskFOUT — text flashes from fallback to web font
KFO7CnqEu92Fr1ME7kSn66a...woff2swap
Size0 KB
Load time14 ms
Start1.2 s
RiskFOUT — text flashes from fallback to web font
KFO7CnqEu92Fr1ME7kSn66a...woff2swap
Size0 KB
Load time17 ms
Start1.2 s
RiskFOUT — text flashes from fallback to web font
KFO7CnqEu92Fr1ME7kSn66a...woff2swap
Size0 KB
Load time19 ms
Start1.2 s
RiskFOUT — text flashes from fallback to web font
KFO7CnqEu92Fr1ME7kSn66a...woff2swap
Size0 KB
Load time18 ms
Start1.2 s
RiskFOUT — text flashes from fallback to web font
ieVl2ZhZI2eCN5jzbjEETS9...woff2swap
Size45 KB
Load time10 ms
Start1.2 s
RiskFOUT — text flashes from fallback to web font
ieVl2ZhZI2eCN5jzbjEETS9...woff2swap
Size0 KB
Load time15 ms
Start1.2 s
RiskFOUT — text flashes from fallback to web font
ieVl2ZhZI2eCN5jzbjEETS9...woff2swap
Size0 KB
Load time17 ms
Start1.2 s
RiskFOUT — text flashes from fallback to web font
KFO7CnqEu92Fr1ME7kSn66a...woff2swap
Size35 KB
Load time11 ms
Start1.9 s
RiskFOUT — 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
No optimization needed
PASS
No optimization needed
Info::
✓
No resource hint issues
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
Network Waterfall
138 requests over 2782ms
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-party10467ms · 660KB · $139/mo
Script
Category
Execution
Transfer
Unused
Monthly Cost
Verdict
www.marinetraffic.com
www.marinetraffic.com
Other
4533ms
25 KB
—
$60/mo
Costly
www.marinetraffic.com
www.marinetraffic.com
Other
1589ms
50 KB
56%
$21/mo
Costly
www.marinetraffic.com
www.marinetraffic.com
Other
1436ms
49 KB
—
$19/mo
Costly
Unattributable
Unattributable
Other
744ms
0 KB
—
$10/mo
Costly
www.marinetraffic.com
www.marinetraffic.com
Other
327ms
3 KB
—
$4/mo
Costly
www.marinetraffic.com
www.marinetraffic.com
Other
305ms
0 KB
—
$4/mo
Costly
cmp.inmobi.com
cmp.inmobi.com
Other
304ms
73 KB
41%
$4/mo
Costly
www.marinetraffic.com
www.marinetraffic.com
Other
251ms
50 KB
—
$3/mo
Costly
cmp.inmobi.com
cmp.inmobi.com
Other
228ms
44 KB
—
$3/mo
Costly
www.marinetraffic.com
www.marinetraffic.com
Other
172ms
40 KB
77%
$2/mo
Optional
www.marinetraffic.com
www.marinetraffic.com
Other
139ms
17 KB
—
$2/mo
Optional
www.marinetraffic.com
www.marinetraffic.com
Other
120ms
17 KB
—
$2/mo
Optional
www.marinetraffic.com
www.marinetraffic.com
Other
77ms
37 KB
85%
$1/mo
Optional
www.marinetraffic.com
www.marinetraffic.com
Other
66ms
44 KB
—
$1/mo
Optional
www.marinetraffic.com
www.marinetraffic.com
Other
63ms
8 KB
—
$1/mo
Optional
www.marinetraffic.com
www.marinetraffic.com
Other
61ms
147 KB
77%
$1/mo
Optional
www.marinetraffic.com
www.marinetraffic.com
Other
53ms
54 KB
—
$1/mo
Optional
www.marinetraffic.com
Other
Costly
Execution4533ms
Transfer25 KB
Monthly Cost$60/mo
www.marinetraffic.com
Other
Costly
Execution1589ms
Transfer50 KB
Unused56%
Monthly Cost$21/mo
www.marinetraffic.com
Other
Costly
Execution1436ms
Transfer49 KB
Monthly Cost$19/mo
Unattributable
Other
Costly
Execution744ms
Transfer0 KB
Monthly Cost$10/mo
www.marinetraffic.com
Other
Costly
Execution327ms
Transfer3 KB
Monthly Cost$4/mo
www.marinetraffic.com
Other
Costly
Execution305ms
Transfer0 KB
Monthly Cost$4/mo
cmp.inmobi.com
Other
Costly
Execution304ms
Transfer73 KB
Unused41%
Monthly Cost$4/mo
www.marinetraffic.com
Other
Costly
Execution251ms
Transfer50 KB
Monthly Cost$3/mo
cmp.inmobi.com
Other
Costly
Execution228ms
Transfer44 KB
Monthly Cost$3/mo
www.marinetraffic.com
Other
Optional
Execution172ms
Transfer40 KB
Unused77%
Monthly Cost$2/mo
www.marinetraffic.com
Other
Optional
Execution139ms
Transfer17 KB
Monthly Cost$2/mo
www.marinetraffic.com
Other
Optional
Execution120ms
Transfer17 KB
Monthly Cost$2/mo
www.marinetraffic.com
Other
Optional
Execution77ms
Transfer37 KB
Unused85%
Monthly Cost$1/mo
www.marinetraffic.com
Other
Optional
Execution66ms
Transfer44 KB
Monthly Cost$1/mo
www.marinetraffic.com
Other
Optional
Execution63ms
Transfer8 KB
Monthly Cost$1/mo
www.marinetraffic.com
Other
Optional
Execution61ms
Transfer147 KB
Unused77%
Monthly Cost$1/mo
www.marinetraffic.com
Other
Optional
Execution53ms
Transfer54 KB
Monthly Cost$1/mo
These scripts may cost more than they're worth
www.marinetraffic.com adds 4533ms and costs ~$60/month
www.marinetraffic.com adds 1589ms and costs ~$21/month
www.marinetraffic.com adds 1436ms and costs ~$19/month
Unattributable adds 744ms and costs ~$10/month
www.marinetraffic.com adds 327ms and costs ~$4/month
www.marinetraffic.com adds 305ms and costs ~$4/month
cmp.inmobi.com adds 304ms and costs ~$4/month
www.marinetraffic.com adds 251ms and costs ~$3/month
cmp.inmobi.com adds 228ms and costs ~$3/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.marinetraffic.com takes 4533ms 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.marinetraffic.com takes 1589ms 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
56% of www.marinetraffic.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
www.marinetraffic.com takes 1436ms 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 744ms 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.marinetraffic.com takes 327ms 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.marinetraffic.com takes 305ms 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
cmp.inmobi.com takes 304ms 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.marinetraffic.com 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
cmp.inmobi.com takes 228ms 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
77% of www.marinetraffic.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
85% of www.marinetraffic.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
77% of www.marinetraffic.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.