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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
2
REVIEW
3
PASS
1
INFO
0
Device:
Mobile Desktop
Checks
6
1 PASS 3 REVIEW 2 FIX
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::
AWS: Renewable energy varies by region; committed to 100% by 2025
Info::
AWS CloudFront: Renewable varies by edge location
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 AWS✗CDN AWS CloudFront✗

AWS: Renewable energy varies by region; committed to 100% by 2025

AWS CloudFront: Renewable varies by edge location

Based on known provider commitments. Verify at thegreenwebfoundation.org

D
Carbon Budget
Action
51th percentile
FIX
51th percentile
Warning::
0.67g CO2 — above the median website (0.60g)
Heavier than an estimated 49% of websites. Reducing page weight, optimizing images, and removing unused JavaScript would lower the carbon footprint. See the Performance tab.
Info::
Estimated 51th percentile
Compared to: top 10% = 0.20g, target = 0.50g, median = 0.60g per page view.
Top 10%
Target
Median website

0.67g

51st percentile

Cleaner than 49% of websites

✗ Above the median website

vs Median 11% more
vs Target 34% more
B
CO2 Per Page Load
0.67g CO2 per view
REVIEW
0.67g CO2 per view
Info::
0.67g CO2 per page view
This page transfers 2.4 MB, producing an estimated 0.67g of CO2 per visit using the Sustainable Web Design model (v4). Breakdown: data center 0.12g, network 0.12g, end-user device 0.43g.
Got: 0.67g CO2 Expected: < 0.50g (sustainability target)
Info::
At 10,000 monthly views: 80.2 kg CO2/year
With 10,000 page views per month, this page would generate approximately 80.2 kg of CO2 annually — equivalent to charging 10026 smartphones.

0.67g

Carbon Footprint per page view

✗ Above sustainability target (0.50g)

Cleaner than 49% of websites

Sustainable Web Design model v4 · Page size: 2.4 MB

Your site
0.67g
Top 10%
0.20g
Target
0.50g
Median website
0.60g

Energy Breakdown

Data center
0.12g
Network
0.12g
End-user device
0.43g
At 10,000 monthly views: Monthly: 6.7 kg · Annual: 80.2 kg · ≈ 10026 smartphone charges
C
Transfer Efficiency
Action
67% efficient
REVIEW
67% efficient
Warning::
Transfer efficiency: 67%
An estimated 793 KB (33%) could be eliminated: 0 KB via better compression, 0 KB via modern image formats, 793 KB of unused JavaScript. This wasted data produces 0.22g of unnecessary CO2 per page view.
67% efficient

Total waste: 793 KB (33% of page weight)

Unused JS 793 KB

0.22g unnecessary CO2 per visit

Actual transfer 2416 KB
Theoretical minimum 1623 KB
Potential savings 793 KB (0.22g 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
96% cached
PASS
96% cached
Info::
96% reduction on repeat visits
Returning visitors download only 100 KB (vs 2416 KB first visit). 130 of 132 resources are served from browser cache, saving 0.64g CO2 per repeat visit.
Info::
Repeat visit: 0.03g CO2 (first visit: 0.67g)
First visit
2416 KB
Repeat visit
100 KB

96% reduction on repeat visits

Saving 0.64g CO2 per returning visitor

130 resources served from cache · 2 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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