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Sustainability

· 6 checks — CO2 emissions, green hosting, repeat-visit weight, carbon budget, and transfer efficiency rolled into one auditable list.
SCORE
64
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
1.19g CO2 per view
FIX
1.19g CO2 per view
Warning::
1.19g CO2 per page view
This page transfers 4.2 MB, producing an estimated 1.19g of CO2 per visit using the Sustainable Web Design model (v4). Breakdown: data center 0.22g, network 0.21g, end-user device 0.76g.
Got: 1.19g CO2 Expected: < 0.50g (sustainability target)
Info::
At 10,000 monthly views: 142.5 kg CO2/year
With 10,000 page views per month, this page would generate approximately 142.5 kg of CO2 annually — equivalent to charging 17812 smartphones.

1.19g

Carbon Footprint per page view

✗ Above sustainability target (0.50g)

Cleaner than 34% of websites

Sustainable Web Design model v4 · Page size: 4.2 MB

Your site
1.19g
Top 10%
0.20g
Target
0.50g
Median website
0.60g

Energy Breakdown

Data center
0.22g
Network
0.21g
End-user device
0.76g
At 10,000 monthly views: Monthly: 11.9 kg · Annual: 142.5 kg · ≈ 17812 smartphone charges
D
Green Hosting
Action
Not green
FIX
Not green
Info::
No confirmed renewable energy commitment detected
Consider providers like Cloudflare, Google Cloud, or Vercel that match 100% of their energy use with renewables.
Info::
Azure: Microsoft is carbon-negative; Azure renewable varies by region
Info::
Azure CDN: Inherits Azure regional renewable mix
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 HostingNot Green Hosted
Hosting Azure✗CDN Azure CDN✗

Azure: Microsoft is carbon-negative; Azure renewable varies by region

Azure CDN: Inherits Azure regional renewable mix

Based on known provider commitments. Verify at thegreenwebfoundation.org

D
Carbon Budget
Action
66th percentile
FIX
66th percentile
Warning::
1.19g CO2 — above the median website (0.60g)
Heavier than an estimated 34% of websites. Reducing page weight, optimizing images, and removing unused JavaScript would lower the carbon footprint. See the Performance tab.
Info::
Estimated 66th percentile
Compared to: top 10% = 0.20g, target = 0.50g, median = 0.60g per page view.
Top 10%
Target
Median website

1.19g

66th percentile

Cleaner than 34% of websites

✗ Above the median website

vs Median 98% more
vs Target 137% more
B
Transfer Efficiency
83% efficient
REVIEW
83% efficient
Info::
Transfer efficiency: 83%
An estimated 735 KB (17%) could be eliminated: 0 KB via better compression, 0 KB via modern image formats, 735 KB of unused JavaScript. This wasted data produces 0.20g of unnecessary CO2 per page view.
83% efficient

Total waste: 735 KB (17% of page weight)

Unused JS 735 KB

0.20g unnecessary CO2 per visit

Actual transfer 4293 KB
Theoretical minimum 3558 KB
Potential savings 735 KB (0.20g 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
99% cached
PASS
99% cached
Info::
99% reduction on repeat visits
Returning visitors download only 51 KB (vs 4293 KB first visit). 43 of 44 resources are served from browser cache, saving 1.17g CO2 per repeat visit.
Info::
Repeat visit: 0.01g CO2 (first visit: 1.19g)
First visit
4293 KB
Repeat visit
51 KB

99% reduction on repeat visits

Saving 1.17g CO2 per returning visitor

43 resources served from cache · 1 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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