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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
68
GRADE
D
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
1.15g CO2 per view
FIX
1.15g CO2 per view
Warning::
1.15g CO2 per page view
This page transfers 4.0 MB, producing an estimated 1.15g of CO2 per visit using the Sustainable Web Design model (v4). Breakdown: data center 0.21g, network 0.20g, end-user device 0.74g.
Got: 1.15g CO2 Expected: < 0.50g (sustainability target)
Info::
At 10,000 monthly views: 137.4 kg CO2/year
With 10,000 page views per month, this page would generate approximately 137.4 kg of CO2 annually — equivalent to charging 17179 smartphones.

1.15g

Carbon Footprint per page view

✗ Above sustainability target (0.50g)

Cleaner than 35% of websites

Sustainable Web Design model v4 · Page size: 4.0 MB

Your site
1.15g
Top 10%
0.20g
Target
0.50g
Median website
0.60g

Energy Breakdown

Data center
0.21g
Network
0.20g
End-user device
0.74g
At 10,000 monthly views: Monthly: 11.5 kg · Annual: 137.4 kg · ≈ 17179 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
65th percentile
FIX
65th percentile
Warning::
1.15g CO2 — above the median website (0.60g)
Heavier than an estimated 35% of websites. Reducing page weight, optimizing images, and removing unused JavaScript would lower the carbon footprint. See the Performance tab.
Info::
Estimated 65th percentile
Compared to: top 10% = 0.20g, target = 0.50g, median = 0.60g per page view.
Top 10%
Target
Median website

1.15g

65th percentile

Cleaner than 35% of websites

✗ Above the median website

vs Median 91% more
vs Target 129% 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
100% cached
PASS
100% cached
Info::
100% reduction on repeat visits
Returning visitors download only 9 KB (vs 4141 KB first visit). 51 of 52 resources are served from browser cache, saving 1.14g CO2 per repeat visit.
Info::
Repeat visit: 0.00g CO2 (first visit: 1.15g)
First visit
4141 KB
Repeat visit
9 KB

100% reduction on repeat visits

Saving 1.14g CO2 per returning visitor

51 resources served from cache · 1 resources re-downloaded

A+
Transfer Efficiency
97% efficient
PASS
97% efficient
Info::
Transfer efficiency: 97%
Only 125 KB of potential savings identified. Your page is well-optimized for size.
97% efficient

Total waste: 125 KB (3% of page weight)

Unused JS 125 KB

0.03g unnecessary CO2 per visit

Actual transfer 4141 KB
Theoretical minimum 4015 KB
Potential savings 125 KB (0.03g 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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