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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
2
PASS
3
INFO
0
Device:
Mobile Desktop
Checks
6
3 PASS 2 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
Carbon Budget
37th percentile
REVIEW
37th percentile
Info::
0.47g CO2 — below the sustainability target of 0.50g
Cleaner than an estimated 63% of websites analyzed. This page meets the Web Sustainability Guidelines target.
Info::
Estimated 37th percentile
Compared to: top 10% = 0.20g, target = 0.50g, median = 0.60g per page view.
Top 10%
Target
Median website

0.47g

37th percentile

Cleaner than 63% of websites

✓ Below the Web Sustainability Guidelines target

vs Median 21% cleaner ✓
vs Target 5% cleaner ✓
C
Green Hosting
Action
Whether the site is served from green-energy infrastructure
REVIEW

Green Hosting

No green hosting detected

A
CO2 Per Page Load
0.47g CO2 per view
PASS
0.47g CO2 per view
Info::
0.47g CO2 per page view
This page transfers 1.7 MB, producing an estimated 0.47g of CO2 per visit using the Sustainable Web Design model (v4). Breakdown: data center 0.09g, network 0.08g, end-user device 0.30g.
Got: 0.47g CO2 Expected: < 0.50g (sustainability target)
Info::
At 10,000 monthly views: 56.8 kg CO2/year
With 10,000 page views per month, this page would generate approximately 56.8 kg of CO2 annually — equivalent to charging 7097 smartphones.

0.47g

Carbon Footprint per page view

✓ Below sustainability target (0.50g)

Cleaner than 63% of websites

Sustainable Web Design model v4 · Page size: 1.7 MB

Your site
0.47g
Top 10%
0.20g
Target
0.50g
Median website
0.60g

Energy Breakdown

Data center
0.09g
Network
0.08g
End-user device
0.30g
At 10,000 monthly views: Monthly: 4.7 kg · Annual: 56.8 kg · ≈ 7097 smartphone charges
A+
Repeat Visit Weight
92% cached
PASS
92% cached
Info::
92% reduction on repeat visits
Returning visitors download only 139 KB (vs 1710 KB first visit). 102 of 103 resources are served from browser cache, saving 0.43g CO2 per repeat visit.
Info::
Repeat visit: 0.04g CO2 (first visit: 0.47g)
First visit
1710 KB
Repeat visit
139 KB

92% reduction on repeat visits

Saving 0.43g CO2 per returning visitor

102 resources served from cache · 1 resources re-downloaded

A+
Transfer Efficiency
91% efficient
PASS
91% efficient
Info::
Transfer efficiency: 91%
Only 160 KB of potential savings identified. Your page is well-optimized for size.
91% efficient

Total waste: 160 KB (9% of page weight)

Unused JS 160 KB

0.04g unnecessary CO2 per visit

Actual transfer 1710 KB
Theoretical minimum 1550 KB
Potential savings 160 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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