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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
72
GRADE
C
FIX
3
REVIEW
1
PASS
2
INFO
0
Checks
6
2 PASS 1 REVIEW 3 FIX
F
CO2 Per Page Load
Action
1.67g CO2 per view
FIX
1.67g CO2 per view
Warning::
1.67g CO2 per page view
This page transfers 5.9 MB, producing an estimated 1.67g of CO2 per visit using the Sustainable Web Design model (v4). Breakdown: data center 0.31g, network 0.29g, end-user device 1.07g.
Got: 1.67g CO2 Expected: < 0.50g (sustainability target)
Info::
At 10,000 monthly views: 199.8 kg CO2/year
With 10,000 page views per month, this page would generate approximately 199.8 kg of CO2 annually — equivalent to charging 24977 smartphones.

1.67g

Carbon Footprint per page view

Above sustainability target (0.50g)

Cleaner than 20% of websites

Sustainable Web Design model v4 · Page size: 5.9 MB

Your site
1.67g
Top 10%
0.20g
Target
0.50g
Median website
0.60g

Energy Breakdown

Data center
0.31g
Network
0.29g
End-user device
1.07g
At 10,000 monthly views: Monthly: 16.7 kg · Annual: 199.8 kg · ≈ 24977 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 ServicesCDN Not identified

Based on known provider commitments. Verify at thegreenwebfoundation.org

F
Carbon Budget
Action
80th percentile
FIX
80th percentile
Warning::
1.67g CO2 — above the median website (0.60g)
Heavier than an estimated 20% of websites. Reducing page weight, optimizing images, and removing unused JavaScript would lower the carbon footprint. See the Performance tab.
Info::
Estimated 80th percentile
Compared to: top 10% = 0.20g, target = 0.50g, median = 0.60g per page view.
Top 10%
Target
Median website

1.67g

80th percentile

Cleaner than 20% of websites

Above the median website

vs Median 178% more
vs Target 233% 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 69 KB (vs 6020 KB first visit). 266 of 269 resources are served from browser cache, saving 1.65g CO2 per repeat visit.
Info::
Repeat visit: 0.02g CO2 (first visit: 1.67g)
First visit
6020 KB
Repeat visit
69 KB

99% reduction on repeat visits

Saving 1.65g CO2 per returning visitor

266 resources served from cache · 3 resources re-downloaded

A+
Transfer Efficiency
92% efficient
PASS
92% efficient
Info::
Transfer efficiency: 92%
Only 454 KB of potential savings identified. Your page is well-optimized for size.
92% efficient

Total waste: 454 KB (8% of page weight)

Unused JS 454 KB

0.13g unnecessary CO2 per visit

Actual transfer 6020 KB
Theoretical minimum 5566 KB
Potential savings 454 KB (0.13g 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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