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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
79
GRADE
C
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
1.10g CO2 per view
FIX
1.10g CO2 per view
Warning::
1.10g CO2 per page view
This page transfers 3.9 MB, producing an estimated 1.10g of CO2 per visit using the Sustainable Web Design model (v4). Breakdown: data center 0.20g, network 0.19g, end-user device 0.71g.
Got: 1.10g CO2 Expected: < 0.50g (sustainability target)
Info::
At 10,000 monthly views: 132.5 kg CO2/year
With 10,000 page views per month, this page would generate approximately 132.5 kg of CO2 annually — equivalent to charging 16561 smartphones.

1.10g

Carbon Footprint per page view

✗ Above sustainability target (0.50g)

Cleaner than 36% of websites

Sustainable Web Design model v4 · Page size: 3.9 MB

Your site
1.10g
Top 10%
0.20g
Target
0.50g
Median website
0.60g

Energy Breakdown

Data center
0.20g
Network
0.19g
End-user device
0.71g
At 10,000 monthly views: Monthly: 11.0 kg · Annual: 132.5 kg · ≈ 16561 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 Microsoft IIS✗CDN Not identified✗

Based on known provider commitments. Verify at thegreenwebfoundation.org

D
Carbon Budget
Action
64th percentile
FIX
64th percentile
Warning::
1.10g CO2 — above the median website (0.60g)
Heavier than an estimated 36% of websites. Reducing page weight, optimizing images, and removing unused JavaScript would lower the carbon footprint. See the Performance tab.
Info::
Estimated 64th percentile
Compared to: top 10% = 0.20g, target = 0.50g, median = 0.60g per page view.
Top 10%
Target
Median website

1.10g

64th percentile

Cleaner than 36% of websites

✗ Above the median website

vs Median 84% more
vs Target 121% 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 53 KB (vs 3992 KB first visit). 59 of 60 resources are served from browser cache, saving 1.09g CO2 per repeat visit.
Info::
Repeat visit: 0.01g CO2 (first visit: 1.10g)
First visit
3992 KB
Repeat visit
53 KB

99% reduction on repeat visits

Saving 1.09g CO2 per returning visitor

59 resources served from cache · 1 resources re-downloaded

A+
Transfer Efficiency
98% efficient
PASS
98% efficient
Info::
Transfer efficiency: 98%
Only 69 KB of potential savings identified. Your page is well-optimized for size.
98% efficient

Total waste: 69 KB (2% of page weight)

Unused JS 69 KB

0.02g unnecessary CO2 per visit

Actual transfer 3992 KB
Theoretical minimum 3923 KB
Potential savings 69 KB (0.02g 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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