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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
54
GRADE
F
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
1.05g CO2 per view
FIX
1.05g CO2 per view
Warning::
1.05g CO2 per page view
This page transfers 3.7 MB, producing an estimated 1.05g of CO2 per visit using the Sustainable Web Design model (v4). Breakdown: data center 0.19g, network 0.18g, end-user device 0.67g.
Got: 1.05g CO2 Expected: < 0.50g (sustainability target)
Info::
At 10,000 monthly views: 126.1 kg CO2/year
With 10,000 page views per month, this page would generate approximately 126.1 kg of CO2 annually — equivalent to charging 15756 smartphones.

1.05g

Carbon Footprint per page view

✗ Above sustainability target (0.50g)

Cleaner than 38% of websites

Sustainable Web Design model v4 · Page size: 3.7 MB

Your site
1.05g
Top 10%
0.20g
Target
0.50g
Median website
0.60g

Energy Breakdown

Data center
0.19g
Network
0.18g
End-user device
0.67g
At 10,000 monthly views: Monthly: 10.5 kg · Annual: 126.1 kg · ≈ 15756 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

D
Carbon Budget
Action
62th percentile
FIX
62th percentile
Warning::
1.05g CO2 — above the median website (0.60g)
Heavier than an estimated 38% of websites. Reducing page weight, optimizing images, and removing unused JavaScript would lower the carbon footprint. See the Performance tab.
Info::
Estimated 62th percentile
Compared to: top 10% = 0.20g, target = 0.50g, median = 0.60g per page view.
Top 10%
Target
Median website

1.05g

62nd percentile

Cleaner than 38% of websites

✗ Above the median website

vs Median 75% more
vs Target 110% more
B
Transfer Efficiency
87% efficient
REVIEW
87% efficient
Info::
Transfer efficiency: 87%
An estimated 498 KB (13%) could be eliminated: 0 KB via better compression, 0 KB via modern image formats, 498 KB of unused JavaScript. This wasted data produces 0.14g of unnecessary CO2 per page view.
87% efficient

Total waste: 498 KB (13% of page weight)

Unused JS 498 KB

0.14g unnecessary CO2 per visit

Actual transfer 3798 KB
Theoretical minimum 3299 KB
Potential savings 498 KB (0.14g 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
97% cached
PASS
97% cached
Info::
97% reduction on repeat visits
Returning visitors download only 100 KB (vs 3798 KB first visit). 238 of 263 resources are served from browser cache, saving 1.02g CO2 per repeat visit.
Info::
Repeat visit: 0.03g CO2 (first visit: 1.05g)
First visit
3798 KB
Repeat visit
100 KB

97% reduction on repeat visits

Saving 1.02g CO2 per returning visitor

238 resources served from cache · 25 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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