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https://sydney.edu.au

Sustainability

· 6 checks — CO2 emissions, green hosting, repeat-visit weight, carbon budget, and transfer efficiency rolled into one auditable list.
SCORE
62
GRADE
D
FIX
3
REVIEW
2
PASS
1
INFO
0
Device:
Mobile Desktop
Checks
6
1 PASS 2 REVIEW 3 FIX
D
CO2 Per Page Load
Action
1.21g CO2 per view
FIX
1.21g CO2 per view
Warning::
1.21g CO2 per page view
This page transfers 4.3 MB, producing an estimated 1.21g of CO2 per visit using the Sustainable Web Design model (v4). Breakdown: data center 0.22g, network 0.21g, end-user device 0.78g.
Got: 1.21g CO2 Expected: < 0.50g (sustainability target)
Info::
At 10,000 monthly views: 145.5 kg CO2/year
With 10,000 page views per month, this page would generate approximately 145.5 kg of CO2 annually — equivalent to charging 18185 smartphones.

1.21g

Carbon Footprint per page view

✗ Above sustainability target (0.50g)

Cleaner than 33% of websites

Sustainable Web Design model v4 · Page size: 4.3 MB

Your site
1.21g
Top 10%
0.20g
Target
0.50g
Median website
0.60g

Energy Breakdown

Data center
0.22g
Network
0.21g
End-user device
0.78g
At 10,000 monthly views: Monthly: 12.1 kg · Annual: 145.5 kg · ≈ 18185 smartphone charges
D
Green Hosting
Action
Unknown
FIX
Unknown
Info::
Hosting provider could not be identified
Without knowing the provider, we cannot determine their energy sourcing. Check with your hosting provider about their renewable energy commitments.
Info::
Green hosting status based on known provider commitments
Green hosting detection uses a curated database of provider renewable energy commitments. This is not a real-time verification. For authoritative checks, visit thegreenwebfoundation.org.
Green HostingUnable to Determine
Hosting Not identified✗CDN Not identified✗

Based on known provider commitments. Verify at thegreenwebfoundation.org

D
Carbon Budget
Action
67th percentile
FIX
67th percentile
Warning::
1.21g CO2 — above the median website (0.60g)
Heavier than an estimated 33% of websites. Reducing page weight, optimizing images, and removing unused JavaScript would lower the carbon footprint. See the Performance tab.
Info::
Estimated 67th percentile
Compared to: top 10% = 0.20g, target = 0.50g, median = 0.60g per page view.
Top 10%
Target
Median website

1.21g

67th percentile

Cleaner than 33% of websites

✗ Above the median website

vs Median 102% more
vs Target 142% more
C
Transfer Efficiency
Action
70% efficient
REVIEW
70% efficient
Warning::
Transfer efficiency: 70%
An estimated 1319 KB (30%) could be eliminated: 0 KB via better compression, 0 KB via modern image formats, 1319 KB of unused JavaScript. This wasted data produces 0.37g of unnecessary CO2 per page view.
70% efficient

Total waste: 1319 KB (30% of page weight)

Unused JS 1319 KB

0.37g unnecessary CO2 per visit

Actual transfer 4383 KB
Theoretical minimum 3063 KB
Potential savings 1319 KB (0.37g CO2)

See Deep Analysis sections above for specific optimizations.

C
Green Hosting
Action
Whether the site is served from green-energy infrastructure
REVIEW

Green Hosting

No green hosting detected

A+
Repeat Visit Weight
100% cached
PASS
100% cached
Info::
100% reduction on repeat visits
Returning visitors download only 15 KB (vs 4383 KB first visit). 179 of 185 resources are served from browser cache, saving 1.21g CO2 per repeat visit.
Info::
Repeat visit: 0.00g CO2 (first visit: 1.21g)
First visit
4383 KB
Repeat visit
15 KB

100% reduction on repeat visits

Saving 1.21g CO2 per returning visitor

179 resources served from cache · 6 resources re-downloaded

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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