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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
2
PASS
1
INFO
0
Device:
Mobile Desktop
Checks
6
1 PASS 2 REVIEW 3 FIX
D
CO2 Per Page Load
Action
1.49g CO2 per view
FIX
1.49g CO2 per view
Warning::
1.49g CO2 per page view
This page transfers 5.3 MB, producing an estimated 1.49g of CO2 per visit using the Sustainable Web Design model (v4). Breakdown: data center 0.28g, network 0.26g, end-user device 0.96g.
Got: 1.49g CO2 Expected: < 0.50g (sustainability target)
Info::
At 10,000 monthly views: 179.4 kg CO2/year
With 10,000 page views per month, this page would generate approximately 179.4 kg of CO2 annually — equivalent to charging 22423 smartphones.

1.49g

Carbon Footprint per page view

✗ Above sustainability target (0.50g)

Cleaner than 25% of websites

Sustainable Web Design model v4 · Page size: 5.3 MB

Your site
1.49g
Top 10%
0.20g
Target
0.50g
Median website
0.60g

Energy Breakdown

Data center
0.28g
Network
0.26g
End-user device
0.96g
At 10,000 monthly views: Monthly: 14.9 kg · Annual: 179.4 kg · ≈ 22423 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
75th percentile
FIX
75th percentile
Warning::
1.49g CO2 — above the median website (0.60g)
Heavier than an estimated 25% of websites. Reducing page weight, optimizing images, and removing unused JavaScript would lower the carbon footprint. See the Performance tab.
Info::
Estimated 75th percentile
Compared to: top 10% = 0.20g, target = 0.50g, median = 0.60g per page view.
Top 10%
Target
Median website

1.49g

75th percentile

Cleaner than 25% of websites

✗ Above the median website

vs Median 149% more
vs Target 199% more
B
Transfer Efficiency
87% efficient
REVIEW
87% efficient
Info::
Transfer efficiency: 87%
An estimated 687 KB (13%) could be eliminated: 0 KB via better compression, 0 KB via modern image formats, 687 KB of unused JavaScript. This wasted data produces 0.19g of unnecessary CO2 per page view.
87% efficient

Total waste: 687 KB (13% of page weight)

Unused JS 687 KB

0.19g unnecessary CO2 per visit

Actual transfer 5405 KB
Theoretical minimum 4717 KB
Potential savings 687 KB (0.19g 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 128 KB (vs 5405 KB first visit). 149 of 150 resources are served from browser cache, saving 1.46g CO2 per repeat visit.
Info::
Repeat visit: 0.04g CO2 (first visit: 1.49g)
First visit
5405 KB
Repeat visit
128 KB

98% reduction on repeat visits

Saving 1.46g CO2 per returning visitor

149 resources served from cache · 1 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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