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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
79
GRADE
C
FIX
1
REVIEW
3
PASS
2
INFO
0
Device:
Mobile Desktop
Checks
6
2 PASS 3 REVIEW 1 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

B
CO2 Per Page Load
0.54g CO2 per view
REVIEW
0.54g CO2 per view
Info::
0.54g CO2 per page view
This page transfers 1.9 MB, producing an estimated 0.54g of CO2 per visit using the Sustainable Web Design model (v4). Breakdown: data center 0.10g, network 0.09g, end-user device 0.35g.
Got: 0.54g CO2 Expected: < 0.50g (sustainability target)
Info::
At 10,000 monthly views: 64.6 kg CO2/year
With 10,000 page views per month, this page would generate approximately 64.6 kg of CO2 annually — equivalent to charging 8070 smartphones.

0.54g

Carbon Footprint per page view

✗ Above sustainability target (0.50g)

Cleaner than 57% of websites

Sustainable Web Design model v4 · Page size: 1.9 MB

Your site
0.54g
Top 10%
0.20g
Target
0.50g
Median website
0.60g

Energy Breakdown

Data center
0.10g
Network
0.09g
End-user device
0.35g
At 10,000 monthly views: Monthly: 5.4 kg · Annual: 64.6 kg · ≈ 8070 smartphone charges
B
Carbon Budget
43th percentile
REVIEW
43th percentile
Info::
0.54g CO2 — below the median website (0.60g)
Better than an estimated 57% of websites, but above the sustainability target of 0.50g. Reducing page weight would help reach the target.
Info::
Estimated 43th percentile
Compared to: top 10% = 0.20g, target = 0.50g, median = 0.60g per page view.
Top 10%
Target
Median website

0.54g

43rd percentile

Cleaner than 57% of websites

✗ Above the median website

vs Median 10% cleaner ✓
vs Target 8% 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
93% cached
PASS
93% cached
Info::
93% reduction on repeat visits
Returning visitors download only 139 KB (vs 1945 KB first visit). 115 of 116 resources are served from browser cache, saving 0.50g CO2 per repeat visit.
Info::
Repeat visit: 0.04g CO2 (first visit: 0.54g)
First visit
1945 KB
Repeat visit
139 KB

93% reduction on repeat visits

Saving 0.50g CO2 per returning visitor

115 resources served from cache · 1 resources re-downloaded

A+
Transfer Efficiency
92% efficient
PASS
92% efficient
Info::
Transfer efficiency: 92%
Only 161 KB of potential savings identified. Your page is well-optimized for size.
92% efficient

Total waste: 161 KB (8% of page weight)

Unused JS 161 KB

0.04g unnecessary CO2 per visit

Actual transfer 1945 KB
Theoretical minimum 1784 KB
Potential savings 161 KB (0.04g 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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