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.
C
Image Optimization
Action
52 images, 0 KB saveable
REVIEW
52 images, 0 KB saveable
Warning::
!
https://www.uow.edu.au/assets/logos/logo-svgs/logo... is missing width/height — may cause layout shift
Set explicit width and height to prevent CLS.
Warning::
!
https://pxl-uoweduau.terminalfour.net/prod01/chann... is missing width/height — may cause layout shift
Set explicit width and height to prevent CLS.
Warning::
!
https://pxl-uoweduau.terminalfour.net/prod01/chann... is missing width/height — may cause layout shift
Set explicit width and height to prevent CLS.
Warning::
!
https://www.uow.edu.au/assets/logos/footer/Reconci... is missing width/height — may cause layout shift
Set explicit width and height to prevent CLS.
Warning::
!
https://pxl-uoweduau.terminalfour.net/fit-in/600x3... is missing width/height — may cause layout shift
Set explicit width and height to prevent CLS.
Warning::
!
https://pxl-uoweduau.terminalfour.net/fit-in/600x3... is missing width/height — may cause layout shift
Set explicit width and height to prevent CLS.
Warning::
!
https://pxl-uoweduau.terminalfour.net/prod01/chann... is missing width/height — may cause layout shift
Set explicit width and height to prevent CLS.
Warning::
!
https://www.uow.edu.au/assets/logos/footer/BFW-acc... is missing width/height — may cause layout shift
Set explicit width and height to prevent CLS.
Warning::
!
https://pxl-uoweduau.terminalfour.net/fit-in/600x3... is missing width/height — may cause layout shift
Set explicit width and height to prevent CLS.
Warning::
!
https://pxl-uoweduau.terminalfour.net/prod01/chann... is missing width/height — may cause layout shift
Set explicit width and height to prevent CLS.
Warning::
!
https://pxl-uoweduau.terminalfour.net/prod01/chann... is missing width/height — may cause layout shift
Set explicit width and height to prevent CLS.
Warning::
!
https://pxl-uoweduau.terminalfour.net/prod01/chann... is missing width/height — may cause layout shift
Set explicit width and height to prevent CLS.
Warning::
!
https://pxl-uoweduau.terminalfour.net/prod01/chann... is missing width/height — may cause layout shift
Set explicit width and height to prevent CLS.
Warning::
!
https://pxl-uoweduau.terminalfour.net/prod01/chann... is missing width/height — may cause layout shift
Set explicit width and height to prevent CLS.
Warning::
!
https://pxl-uoweduau.terminalfour.net/prod01/chann... is missing width/height — may cause layout shift
Set explicit width and height to prevent CLS.
Warning::
!
https://pxl-uoweduau.terminalfour.net/fit-in/600x3... is missing width/height — may cause layout shift
Set explicit width and height to prevent CLS.
Warning::
!
https://pxl-uoweduau.terminalfour.net/prod01/chann... is missing width/height — may cause layout shift
Set explicit width and height to prevent CLS.
Warning::
!
https://pxl-uoweduau.terminalfour.net/prod01/chann... is missing width/height — may cause layout shift
Set explicit width and height to prevent CLS.
Warning::
!
https://www.uow.edu.au/assets/logos/footer/2023-26... is missing width/height — may cause layout shift
Set explicit width and height to prevent CLS.
Warning::
!
https://pxl-uoweduau.terminalfour.net/fit-in/600x3... is missing width/height — may cause layout shift
Set explicit width and height to prevent CLS.
Warning::
!
https://pxl-uoweduau.terminalfour.net/fit-in/600x3... is missing width/height — may cause layout shift
Set explicit width and height to prevent CLS.
Warning::
!
https://pxl-uoweduau.terminalfour.net/prod01/chann... is missing width/height — may cause layout shift
Set explicit width and height to prevent CLS.
Warning::
!
https://pxl-uoweduau.terminalfour.net/prod01/chann... is missing width/height — may cause layout shift
Set explicit width and height to prevent CLS.
Warning::
!
https://pxl-uoweduau.terminalfour.net/prod01/chann... is missing width/height — may cause layout shift
Set explicit width and height to prevent CLS.
Warning::
!
https://pxl-uoweduau.terminalfour.net/prod01/chann... is missing width/height — may cause layout shift
Set explicit width and height to prevent CLS.
Warning::
!
https://pxl-uoweduau.terminalfour.net/prod01/chann... is missing width/height — may cause layout shift
Set explicit width and height to prevent CLS.
Warning::
!
https://pxl-uoweduau.terminalfour.net/prod01/chann... is missing width/height — may cause layout shift
Set explicit width and height to prevent CLS.
52images501 KB
0oversized-0 KB
40legacy format
27missing 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
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
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
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
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
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
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
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
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
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
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
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
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
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
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
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
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
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
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
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
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
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
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
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
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
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
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
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
2 fonts (43 KB)
PASS
2 fonts (43 KB)
Info::
i
2 font(s) use font-display: swap (FOUT risk but functional)
Web fonts
2
43 KB total
Render-blocking
0
of 2
Dominant font-display
swap
Most common across fonts
Font loading timeline
TransferFOIT (block)FOUT (swap)
woff2;base64,d09GMgABAA...woff2swap
Size8 KB
Load time112 ms
Start3.3 s
RiskFOUT — text flashes from fallback to web font
JTUSjIg1_i6t8kCHKm459Wl...woff2swap
Size35 KB
Load time41 ms
Start3.4 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
Network Waterfall
110 requests over 7111ms
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-party4877ms · 1613KB · A$84/mo
Script
Category
Execution
Transfer
Unused
Monthly Cost
Verdict
Unattributable
Unattributable
Other
962ms
0 KB
—
A$17/mo
Costly
Google Tag Manager
www.googletagmanager.com
Tag Manager
688ms
186 KB
33%
A$12/mo
Costly
www.uow.edu.au
www.uow.edu.au
Other
490ms
12 KB
—
A$8/mo
Costly
Google Tag Manager
www.googletagmanager.com
Tag Manager
327ms
166 KB
38%
A$6/mo
Costly
Facebook Pixel
connect.facebook.net
Advertising
321ms
129 KB
29%
A$6/mo
Costly
Google Tag Manager
www.googletagmanager.com
Tag Manager
308ms
144 KB
43%
A$5/mo
Costly
Google Tag Manager
www.googletagmanager.com
Tag Manager
272ms
170 KB
40%
A$5/mo
Costly
analytics.tiktok.com
analytics.tiktok.com
Other
238ms
122 KB
53%
A$4/mo
Costly
Google Tag Manager
www.googletagmanager.com
Tag Manager
217ms
144 KB
44%
A$4/mo
Costly
Google Tag Manager
www.googletagmanager.com
Tag Manager
208ms
137 KB
48%
A$4/mo
Costly
www.redditstatic.com
www.redditstatic.com
Other
189ms
19 KB
—
A$3/mo
Optional
www.uow.edu.au
www.uow.edu.au
Other
161ms
30 KB
—
A$3/mo
Optional
Facebook Pixel
connect.facebook.net
Advertising
121ms
97 KB
34%
A$2/mo
Optional
www.uow.edu.au
www.uow.edu.au
Other
94ms
77 KB
67%
A$2/mo
Optional
analytics.tiktok.com
analytics.tiktok.com
Other
83ms
106 KB
78%
A$1/mo
Optional
jsDelivr
cdn.jsdelivr.net
CDN
81ms
36 KB
73%
A$1/mo
Optional
Facebook Pixel
connect.facebook.net
Advertising
60ms
18 KB
—
A$1/mo
Optional
siteimproveanalytics.com
siteimproveanalytics.com
Other
57ms
21 KB
—
A$1/mo
Optional
Unattributable
Other
Costly
Execution962ms
Transfer0 KB
Monthly CostA$17/mo
Google Tag Manager
Tag Manager
Costly
Execution688ms
Transfer186 KB
Unused33%
Monthly CostA$12/mo
www.uow.edu.au
Other
Costly
Execution490ms
Transfer12 KB
Monthly CostA$8/mo
Google Tag Manager
Tag Manager
Costly
Execution327ms
Transfer166 KB
Unused38%
Monthly CostA$6/mo
Facebook Pixel
Advertising
Costly
Execution321ms
Transfer129 KB
Unused29%
Monthly CostA$6/mo
Google Tag Manager
Tag Manager
Costly
Execution308ms
Transfer144 KB
Unused43%
Monthly CostA$5/mo
Google Tag Manager
Tag Manager
Costly
Execution272ms
Transfer170 KB
Unused40%
Monthly CostA$5/mo
analytics.tiktok.com
Other
Costly
Execution238ms
Transfer122 KB
Unused53%
Monthly CostA$4/mo
Google Tag Manager
Tag Manager
Costly
Execution217ms
Transfer144 KB
Unused44%
Monthly CostA$4/mo
Google Tag Manager
Tag Manager
Costly
Execution208ms
Transfer137 KB
Unused48%
Monthly CostA$4/mo
www.redditstatic.com
Other
Optional
Execution189ms
Transfer19 KB
Monthly CostA$3/mo
www.uow.edu.au
Other
Optional
Execution161ms
Transfer30 KB
Monthly CostA$3/mo
Facebook Pixel
Advertising
Optional
Execution121ms
Transfer97 KB
Unused34%
Monthly CostA$2/mo
www.uow.edu.au
Other
Optional
Execution94ms
Transfer77 KB
Unused67%
Monthly CostA$2/mo
analytics.tiktok.com
Other
Optional
Execution83ms
Transfer106 KB
Unused78%
Monthly CostA$1/mo
jsDelivr
CDN
Optional
Execution81ms
Transfer36 KB
Unused73%
Monthly CostA$1/mo
Facebook Pixel
Advertising
Optional
Execution60ms
Transfer18 KB
Monthly CostA$1/mo
siteimproveanalytics.com
Other
Optional
Execution57ms
Transfer21 KB
Monthly CostA$1/mo
These scripts may cost more than they're worth
Unattributable adds 962ms and costs ~A$17/month
Google Tag Manager adds 688ms and costs ~A$12/month
www.uow.edu.au adds 490ms and costs ~A$8/month
Google Tag Manager adds 327ms and costs ~A$6/month
Facebook Pixel adds 321ms and costs ~A$6/month
Google Tag Manager adds 308ms and costs ~A$5/month
Google Tag Manager adds 272ms and costs ~A$5/month
analytics.tiktok.com adds 238ms and costs ~A$4/month
Google Tag Manager adds 217ms and costs ~A$4/month
Google Tag Manager adds 208ms and costs ~A$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 962ms 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 688ms 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.uow.edu.au takes 490ms 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 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
Facebook Pixel takes 321ms 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 308ms 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 272ms 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 238ms 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 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
Google Tag Manager takes 217ms 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 208ms 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
67% of www.uow.edu.au'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
78% 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
73% of jsDelivr'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.