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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
56
GRADE
D
FIX
4
REVIEW
1
PASS
1
INFO
0
Device:
Mobile Desktop
Checks
6
1 PASS 1 REVIEW 4 FIX
D
CO2 Per Page Load
Action
1.21g CO2 per view
FIX
1.21g CO2 per view
Warning::
1.21g CO2 per page view
This page transfers 4.3 MB, producing an estimated 1.21g of CO2 per visit using the Sustainable Web Design model (v4). Breakdown: data center 0.22g, network 0.21g, end-user device 0.78g.
Got: 1.21g CO2 Expected: < 0.50g (sustainability target)
Info::
At 10,000 monthly views: 145.4 kg CO2/year
With 10,000 page views per month, this page would generate approximately 145.4 kg of CO2 annually — equivalent to charging 18173 smartphones.

1.21g

Carbon Footprint per page view

✗ Above sustainability target (0.50g)

Cleaner than 33% of websites

Sustainable Web Design model v4 · Page size: 4.3 MB

Your site
1.21g
Top 10%
0.20g
Target
0.50g
Median website
0.60g

Energy Breakdown

Data center
0.22g
Network
0.21g
End-user device
0.78g
At 10,000 monthly views: Monthly: 12.1 kg · Annual: 145.4 kg · ≈ 18173 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

D
Carbon Budget
Action
67th percentile
FIX
67th percentile
Warning::
1.21g CO2 — above the median website (0.60g)
Heavier than an estimated 33% of websites. Reducing page weight, optimizing images, and removing unused JavaScript would lower the carbon footprint. See the Performance tab.
Info::
Estimated 67th percentile
Compared to: top 10% = 0.20g, target = 0.50g, median = 0.60g per page view.
Top 10%
Target
Median website

1.21g

67th percentile

Cleaner than 33% of websites

✗ Above the median website

vs Median 102% more
vs Target 142% more
D
Transfer Efficiency
Action
55% efficient
FIX
55% efficient
Warning::
Transfer efficiency: 55%
An estimated 1954 KB (45%) could be eliminated: 0 KB via better compression, 0 KB via modern image formats, 1954 KB of unused JavaScript. This wasted data produces 0.54g of unnecessary CO2 per page view.
55% efficient

Total waste: 1954 KB (45% of page weight)

Unused JS 1954 KB

0.54g unnecessary CO2 per visit

Actual transfer 4380 KB
Theoretical minimum 2425 KB
Potential savings 1954 KB (0.54g 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 156 KB (vs 4380 KB first visit). 217 of 237 resources are served from browser cache, saving 1.17g CO2 per repeat visit.
Info::
Repeat visit: 0.04g CO2 (first visit: 1.21g)
First visit
4380 KB
Repeat visit
156 KB

96% reduction on repeat visits

Saving 1.17g CO2 per returning visitor

217 resources served from cache · 20 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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