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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
Checks
6
1 PASS 2 REVIEW 3 FIX
D
CO2 Per Page Load
Action
1.04g CO2 per view
FIX
1.04g CO2 per view
Warning::
1.04g CO2 per page view
This page transfers 3.7 MB, producing an estimated 1.04g of CO2 per visit using the Sustainable Web Design model (v4). Breakdown: data center 0.19g, network 0.18g, end-user device 0.67g.
Got: 1.04g CO2 Expected: < 0.50g (sustainability target)
Info::
At 10,000 monthly views: 125.1 kg CO2/year
With 10,000 page views per month, this page would generate approximately 125.1 kg of CO2 annually — equivalent to charging 15635 smartphones.

1.04g

Carbon Footprint per page view

Above sustainability target (0.50g)

Cleaner than 38% of websites

Sustainable Web Design model v4 · Page size: 3.7 MB

Your site
1.04g
Top 10%
0.20g
Target
0.50g
Median website
0.60g

Energy Breakdown

Data center
0.19g
Network
0.18g
End-user device
0.67g
At 10,000 monthly views: Monthly: 10.4 kg · Annual: 125.1 kg · ≈ 15635 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::
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 AzureCDN Not identified

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

Based on known provider commitments. Verify at thegreenwebfoundation.org

D
Carbon Budget
Action
62th percentile
FIX
62th percentile
Warning::
1.04g CO2 — above the median website (0.60g)
Heavier than an estimated 38% of websites. Reducing page weight, optimizing images, and removing unused JavaScript would lower the carbon footprint. See the Performance tab.
Info::
Estimated 62th percentile
Compared to: top 10% = 0.20g, target = 0.50g, median = 0.60g per page view.
Top 10%
Target
Median website

1.04g

62nd percentile

Cleaner than 38% of websites

Above the median website

vs Median 74% more
vs Target 108% more
B
Transfer Efficiency
82% efficient
REVIEW
82% efficient
Info::
Transfer efficiency: 82%
An estimated 694 KB (18%) could be eliminated: 0 KB via better compression, 0 KB via modern image formats, 694 KB of unused JavaScript. This wasted data produces 0.19g of unnecessary CO2 per page view.
82% efficient

Total waste: 694 KB (18% of page weight)

Unused JS 694 KB

0.19g unnecessary CO2 per visit

Actual transfer 3769 KB
Theoretical minimum 3074 KB
Potential savings 694 KB (0.19g 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 43 KB (vs 3769 KB first visit). 70 of 71 resources are served from browser cache, saving 1.03g CO2 per repeat visit.
Info::
Repeat visit: 0.01g CO2 (first visit: 1.04g)
First visit
3769 KB
Repeat visit
43 KB

99% reduction on repeat visits

Saving 1.03g CO2 per returning visitor

70 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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