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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
1.86g CO2 per view
FIX
1.86g CO2 per view
Warning::
1.86g CO2 per page view
This page transfers 6.6 MB, producing an estimated 1.86g of CO2 per visit using the Sustainable Web Design model (v4). Breakdown: data center 0.34g, network 0.32g, end-user device 1.19g.
Got: 1.86g CO2 Expected: < 0.50g (sustainability target)
Info::
At 10,000 monthly views: 222.6 kg CO2/year
With 10,000 page views per month, this page would generate approximately 222.6 kg of CO2 annually — equivalent to charging 27826 smartphones.

1.86g

Carbon Footprint per page view

✗ Above sustainability target (0.50g)

Cleaner than 15% of websites

Sustainable Web Design model v4 · Page size: 6.6 MB

Your site
1.86g
Top 10%
0.20g
Target
0.50g
Median website
0.60g

Energy Breakdown

Data center
0.34g
Network
0.32g
End-user device
1.19g
At 10,000 monthly views: Monthly: 18.6 kg · Annual: 222.6 kg · ≈ 27826 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
85th percentile
FIX
85th percentile
Warning::
1.86g CO2 — above the median website (0.60g)
Heavier than an estimated 15% of websites. Reducing page weight, optimizing images, and removing unused JavaScript would lower the carbon footprint. See the Performance tab.
Info::
Estimated 85th percentile
Compared to: top 10% = 0.20g, target = 0.50g, median = 0.60g per page view.
Top 10%
Target
Median website

1.86g

85th percentile

Cleaner than 15% of websites

✗ Above the median website

vs Median 209% more
vs Target 271% 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
99% cached
PASS
99% cached
Info::
99% reduction on repeat visits
Returning visitors download only 33 KB (vs 6707 KB first visit). 68 of 69 resources are served from browser cache, saving 1.85g CO2 per repeat visit.
Info::
Repeat visit: 0.01g CO2 (first visit: 1.86g)
First visit
6707 KB
Repeat visit
33 KB

99% reduction on repeat visits

Saving 1.85g CO2 per returning visitor

68 resources served from cache · 1 resources re-downloaded

A+
Transfer Efficiency
95% efficient
PASS
95% efficient
Info::
Transfer efficiency: 95%
Only 349 KB of potential savings identified. Your page is well-optimized for size.
95% efficient

Total waste: 349 KB (5% of page weight)

Unused JS 349 KB

0.10g unnecessary CO2 per visit

Actual transfer 6707 KB
Theoretical minimum 6357 KB
Potential savings 349 KB (0.10g 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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