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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
1
PASS
2
INFO
0
Device:
Mobile Desktop
Checks
6
2 PASS 1 REVIEW 3 FIX
F
CO2 Per Page Load
Action
5.48g CO2 per view
FIX
5.48g CO2 per view
Critical::
5.48g CO2 per page view
This page transfers 19.4 MB, producing an estimated 5.48g of CO2 per visit using the Sustainable Web Design model (v4). Breakdown: data center 1.02g, network 0.95g, end-user device 3.52g.
Got: 5.48g CO2 Expected: < 0.50g (sustainability target)
Info::
At 10,000 monthly views: 657.8 kg CO2/year
With 10,000 page views per month, this page would generate approximately 657.8 kg of CO2 annually — equivalent to charging 82223 smartphones.

5.48g

Carbon Footprint per page view

✗ Above sustainability target (0.50g)

Cleaner than 5% of websites

Sustainable Web Design model v4 · Page size: 19.4 MB

Your site
5.48g
Top 10%
0.20g
Target
0.50g
Median website
0.60g

Energy Breakdown

Data center
1.02g
Network
0.95g
End-user device
3.52g
At 10,000 monthly views: Monthly: 54.8 kg · Annual: 657.8 kg · ≈ 82223 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

F
Carbon Budget
Action
95th percentile
FIX
95th percentile
Warning::
5.48g CO2 — above the median website (0.60g)
Heavier than an estimated 5% of websites. Reducing page weight, optimizing images, and removing unused JavaScript would lower the carbon footprint. See the Performance tab.
Info::
Estimated 95th percentile
Compared to: top 10% = 0.20g, target = 0.50g, median = 0.60g per page view.
Top 10%
Target
Median website

5.48g

95th percentile

Cleaner than 5% of websites

✗ Above the median website

vs Median 814% more
vs Target 996% 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
100% cached
PASS
100% cached
Info::
100% reduction on repeat visits
Returning visitors download only 78 KB (vs 19820 KB first visit). 167 of 170 resources are served from browser cache, saving 5.46g CO2 per repeat visit.
Info::
Repeat visit: 0.02g CO2 (first visit: 5.48g)
First visit
19820 KB
Repeat visit
78 KB

100% reduction on repeat visits

Saving 5.46g CO2 per returning visitor

167 resources served from cache · 3 resources re-downloaded

A+
Transfer Efficiency
95% efficient
PASS
95% efficient
Info::
Transfer efficiency: 95%
Only 907 KB of potential savings identified. Your page is well-optimized for size.
95% efficient

Total waste: 907 KB (5% of page weight)

Unused JS 907 KB

0.25g unnecessary CO2 per visit

Actual transfer 19820 KB
Theoretical minimum 18912 KB
Potential savings 907 KB (0.25g 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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