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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
1
PASS
2
INFO
0
Device:
Mobile Desktop
Checks
6
2 PASS 1 REVIEW 3 FIX
D
CO2 Per Page Load
Action
1.46g CO2 per view
FIX
1.46g CO2 per view
Warning::
1.46g CO2 per page view
This page transfers 5.1 MB, producing an estimated 1.46g of CO2 per visit using the Sustainable Web Design model (v4). Breakdown: data center 0.27g, network 0.25g, end-user device 0.94g.
Got: 1.46g CO2 Expected: < 0.50g (sustainability target)
Info::
At 10,000 monthly views: 174.9 kg CO2/year
With 10,000 page views per month, this page would generate approximately 174.9 kg of CO2 annually — equivalent to charging 21858 smartphones.

1.46g

Carbon Footprint per page view

✗ Above sustainability target (0.50g)

Cleaner than 26% of websites

Sustainable Web Design model v4 · Page size: 5.1 MB

Your site
1.46g
Top 10%
0.20g
Target
0.50g
Median website
0.60g

Energy Breakdown

Data center
0.27g
Network
0.25g
End-user device
0.94g
At 10,000 monthly views: Monthly: 14.6 kg · Annual: 174.9 kg · ≈ 21858 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
74th percentile
FIX
74th percentile
Warning::
1.46g CO2 — above the median website (0.60g)
Heavier than an estimated 26% of websites. Reducing page weight, optimizing images, and removing unused JavaScript would lower the carbon footprint. See the Performance tab.
Info::
Estimated 74th percentile
Compared to: top 10% = 0.20g, target = 0.50g, median = 0.60g per page view.
Top 10%
Target
Median website

1.46g

74th percentile

Cleaner than 26% of websites

✗ Above the median website

vs Median 143% more
vs Target 191% more
C
Green Hosting
Action
Whether the site is served from green-energy infrastructure
REVIEW

Green Hosting

No green hosting detected

A+
Repeat Visit Weight
99% cached
PASS
99% cached
Info::
99% reduction on repeat visits
Returning visitors download only 62 KB (vs 5268 KB first visit). 65 of 67 resources are served from browser cache, saving 1.44g CO2 per repeat visit.
Info::
Repeat visit: 0.02g CO2 (first visit: 1.46g)
First visit
5268 KB
Repeat visit
62 KB

99% reduction on repeat visits

Saving 1.44g CO2 per returning visitor

65 resources served from cache · 2 resources re-downloaded

A+
Transfer Efficiency
98% efficient
PASS
98% efficient
Info::
Transfer efficiency: 98%
Only 118 KB of potential savings identified. Your page is well-optimized for size.
98% efficient

Total waste: 118 KB (2% of page weight)

Unused JS 118 KB

0.03g unnecessary CO2 per visit

Actual transfer 5268 KB
Theoretical minimum 5150 KB
Potential savings 118 KB (0.03g CO2)

See Deep Analysis sections above for specific optimizations.

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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