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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
64
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
1.09g CO2 per view
FIX
1.09g CO2 per view
Warning::
1.09g CO2 per page view
This page transfers 3.8 MB, producing an estimated 1.09g of CO2 per visit using the Sustainable Web Design model (v4). Breakdown: data center 0.20g, network 0.19g, end-user device 0.70g.
Got: 1.09g CO2 Expected: < 0.50g (sustainability target)
Info::
At 10,000 monthly views: 130.2 kg CO2/year
With 10,000 page views per month, this page would generate approximately 130.2 kg of CO2 annually — equivalent to charging 16278 smartphones.

1.09g

Carbon Footprint per page view

✗ Above sustainability target (0.50g)

Cleaner than 37% of websites

Sustainable Web Design model v4 · Page size: 3.8 MB

Your site
1.09g
Top 10%
0.20g
Target
0.50g
Median website
0.60g

Energy Breakdown

Data center
0.20g
Network
0.19g
End-user device
0.70g
At 10,000 monthly views: Monthly: 10.9 kg · Annual: 130.2 kg · ≈ 16278 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 Apache HTTP Server✗CDN Not identified✗

Based on known provider commitments. Verify at thegreenwebfoundation.org

D
Carbon Budget
Action
63th percentile
FIX
63th percentile
Warning::
1.09g CO2 — above the median website (0.60g)
Heavier than an estimated 37% of websites. Reducing page weight, optimizing images, and removing unused JavaScript would lower the carbon footprint. See the Performance tab.
Info::
Estimated 63th percentile
Compared to: top 10% = 0.20g, target = 0.50g, median = 0.60g per page view.
Top 10%
Target
Median website

1.09g

63rd percentile

Cleaner than 37% of websites

✗ Above the median website

vs Median 81% more
vs Target 117% more
B
Transfer Efficiency
84% efficient
REVIEW
84% efficient
Info::
Transfer efficiency: 84%
An estimated 615 KB (16%) could be eliminated: 0 KB via better compression, 0 KB via modern image formats, 615 KB of unused JavaScript. This wasted data produces 0.17g of unnecessary CO2 per page view.
84% efficient

Total waste: 615 KB (16% of page weight)

Unused JS 615 KB

0.17g unnecessary CO2 per visit

Actual transfer 3923 KB
Theoretical minimum 3308 KB
Potential savings 615 KB (0.17g 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
91% cached
PASS
91% cached
Info::
91% reduction on repeat visits
Returning visitors download only 335 KB (vs 3923 KB first visit). 176 of 183 resources are served from browser cache, saving 0.99g CO2 per repeat visit.
Info::
Repeat visit: 0.09g CO2 (first visit: 1.09g)
First visit
3923 KB
Repeat visit
335 KB

91% reduction on repeat visits

Saving 0.99g CO2 per returning visitor

176 resources served from cache · 7 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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