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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
3
REVIEW
2
PASS
1
INFO
0
Device:
Mobile Desktop
Checks
6
1 PASS 2 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 5.6 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: 191.7 kg CO2/year
With 10,000 page views per month, this page would generate approximately 191.7 kg of CO2 annually — equivalent to charging 23966 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: 5.6 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: 191.7 kg · ≈ 23966 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::
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 Amazon Web Services✗CDN Not identified✗

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 166% more
vs Target 220% more
B
Transfer Efficiency
82% efficient
REVIEW
82% efficient
Info::
Transfer efficiency: 82%
An estimated 1013 KB (18%) could be eliminated: 0 KB via better compression, 0 KB via modern image formats, 1013 KB of unused JavaScript. This wasted data produces 0.28g of unnecessary CO2 per page view.
82% efficient

Total waste: 1013 KB (18% of page weight)

Unused JS 1013 KB

0.28g unnecessary CO2 per visit

Actual transfer 5777 KB
Theoretical minimum 4763 KB
Potential savings 1013 KB (0.28g 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
98% cached
PASS
98% cached
Info::
98% reduction on repeat visits
Returning visitors download only 125 KB (vs 5777 KB first visit). 311 of 321 resources are served from browser cache, saving 1.56g CO2 per repeat visit.
Info::
Repeat visit: 0.03g CO2 (first visit: 1.60g)
First visit
5777 KB
Repeat visit
125 KB

98% reduction on repeat visits

Saving 1.56g CO2 per returning visitor

311 resources served from cache · 10 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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