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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
72
GRADE
C
FIX
3
REVIEW
1
PASS
2
INFO
0
Device:
Mobile Desktop
Checks
6
2 PASS 1 REVIEW 3 FIX
D
CO2 Per Page Load
Action
0.81g CO2 per view
FIX
0.81g CO2 per view
Info::
0.81g CO2 per page view
This page transfers 2.9 MB, producing an estimated 0.81g of CO2 per visit using the Sustainable Web Design model (v4). Breakdown: data center 0.15g, network 0.14g, end-user device 0.52g.
Got: 0.81g CO2 Expected: < 0.50g (sustainability target)
Info::
At 10,000 monthly views: 97.6 kg CO2/year
With 10,000 page views per month, this page would generate approximately 97.6 kg of CO2 annually — equivalent to charging 12196 smartphones.

0.81g

Carbon Footprint per page view

✗ Above sustainability target (0.50g)

Cleaner than 44% of websites

Sustainable Web Design model v4 · Page size: 2.9 MB

Your site
0.81g
Top 10%
0.20g
Target
0.50g
Median website
0.60g

Energy Breakdown

Data center
0.15g
Network
0.14g
End-user device
0.52g
At 10,000 monthly views: Monthly: 8.1 kg · Annual: 97.6 kg · ≈ 12196 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
56th percentile
FIX
56th percentile
Warning::
0.81g CO2 — above the median website (0.60g)
Heavier than an estimated 44% of websites. Reducing page weight, optimizing images, and removing unused JavaScript would lower the carbon footprint. See the Performance tab.
Info::
Estimated 56th percentile
Compared to: top 10% = 0.20g, target = 0.50g, median = 0.60g per page view.
Top 10%
Target
Median website

0.81g

56th percentile

Cleaner than 44% of websites

✗ Above the median website

vs Median 36% more
vs Target 63% more
C
Green Hosting
Action
Whether the site is served from green-energy infrastructure
REVIEW

Green Hosting

No green hosting detected

A+
Repeat Visit Weight
91% cached
PASS
91% cached
Info::
91% reduction on repeat visits
Returning visitors download only 269 KB (vs 2940 KB first visit). 107 of 116 resources are served from browser cache, saving 0.74g CO2 per repeat visit.
Info::
Repeat visit: 0.07g CO2 (first visit: 0.81g)
First visit
2940 KB
Repeat visit
269 KB

91% reduction on repeat visits

Saving 0.74g CO2 per returning visitor

107 resources served from cache · 9 resources re-downloaded

A+
Transfer Efficiency
98% efficient
PASS
98% efficient
Info::
Transfer efficiency: 98%
Only 70 KB of potential savings identified. Your page is well-optimized for size.
98% efficient

Total waste: 70 KB (2% of page weight)

Unused JS 70 KB

0.02g unnecessary CO2 per visit

Actual transfer 2940 KB
Theoretical minimum 2869 KB
Potential savings 70 KB (0.02g CO2)

See Deep Analysis sections above for specific optimizations.

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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