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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
60
GRADE
D
FIX
3
REVIEW
1
PASS
2
INFO
0
Device:
Mobile Desktop
Checks
6
2 PASS 1 REVIEW 3 FIX
F
CO2 Per Page Load
Action
1.60g CO2 per view
FIX
1.60g CO2 per view
Warning::
1.60g CO2 per page view
This page transfers 5.7 MB, producing an estimated 1.60g of CO2 per visit using the Sustainable Web Design model (v4). Breakdown: data center 0.30g, network 0.28g, end-user device 1.03g.
Got: 1.60g CO2 Expected: < 0.50g (sustainability target)
Info::
At 10,000 monthly views: 192.2 kg CO2/year
With 10,000 page views per month, this page would generate approximately 192.2 kg of CO2 annually — equivalent to charging 24029 smartphones.

1.60g

Carbon Footprint per page view

✗ Above sustainability target (0.50g)

Cleaner than 22% of websites

Sustainable Web Design model v4 · Page size: 5.7 MB

Your site
1.60g
Top 10%
0.20g
Target
0.50g
Median website
0.60g

Energy Breakdown

Data center
0.30g
Network
0.28g
End-user device
1.03g
At 10,000 monthly views: Monthly: 16.0 kg · Annual: 192.2 kg · ≈ 24029 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::
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

F
Carbon Budget
Action
78th percentile
FIX
78th percentile
Warning::
1.60g CO2 — above the median website (0.60g)
Heavier than an estimated 22% of websites. Reducing page weight, optimizing images, and removing unused JavaScript would lower the carbon footprint. See the Performance tab.
Info::
Estimated 78th percentile
Compared to: top 10% = 0.20g, target = 0.50g, median = 0.60g per page view.
Top 10%
Target
Median website

1.60g

78th percentile

Cleaner than 22% of websites

✗ Above the median website

vs Median 167% more
vs Target 220% 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
80% cached
PASS
80% cached
Info::
80% reduction on repeat visits
Returning visitors download only 1150 KB (vs 5792 KB first visit). 219 of 232 resources are served from browser cache, saving 1.28g CO2 per repeat visit.
Info::
Repeat visit: 0.32g CO2 (first visit: 1.60g)
First visit
5792 KB
Repeat visit
1150 KB

80% reduction on repeat visits

Saving 1.28g CO2 per returning visitor

219 resources served from cache · 13 resources re-downloaded

A+
Transfer Efficiency
98% efficient
PASS
98% efficient
Info::
Transfer efficiency: 98%
Only 131 KB of potential savings identified. Your page is well-optimized for size.
98% efficient

Total waste: 131 KB (2% of page weight)

Unused JS 131 KB

0.04g unnecessary CO2 per visit

Actual transfer 5792 KB
Theoretical minimum 5660 KB
Potential savings 131 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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