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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
1
REVIEW
4
PASS
1
INFO
0
Device:
Mobile Desktop
Checks
6
1 PASS 4 REVIEW 1 FIX
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::
Azure: Microsoft is carbon-negative; Azure renewable varies by region
Info::
Azure CDN: Inherits Azure regional renewable mix
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 Azure✗CDN Azure CDN✗

Azure: Microsoft is carbon-negative; Azure renewable varies by region

Azure CDN: Inherits Azure regional renewable mix

Based on known provider commitments. Verify at thegreenwebfoundation.org

B
CO2 Per Page Load
0.55g CO2 per view
REVIEW
0.55g CO2 per view
Info::
0.55g CO2 per page view
This page transfers 2.0 MB, producing an estimated 0.55g of CO2 per visit using the Sustainable Web Design model (v4). Breakdown: data center 0.10g, network 0.10g, end-user device 0.35g.
Got: 0.55g CO2 Expected: < 0.50g (sustainability target)
Info::
At 10,000 monthly views: 66.3 kg CO2/year
With 10,000 page views per month, this page would generate approximately 66.3 kg of CO2 annually — equivalent to charging 8285 smartphones.

0.55g

Carbon Footprint per page view

✗ Above sustainability target (0.50g)

Cleaner than 55% of websites

Sustainable Web Design model v4 · Page size: 2.0 MB

Your site
0.55g
Top 10%
0.20g
Target
0.50g
Median website
0.60g

Energy Breakdown

Data center
0.10g
Network
0.10g
End-user device
0.35g
At 10,000 monthly views: Monthly: 5.5 kg · Annual: 66.3 kg · ≈ 8285 smartphone charges
B
Carbon Budget
45th percentile
REVIEW
45th percentile
Info::
0.55g CO2 — below the median website (0.60g)
Better than an estimated 55% of websites, but above the sustainability target of 0.50g. Reducing page weight would help reach the target.
Info::
Estimated 45th percentile
Compared to: top 10% = 0.20g, target = 0.50g, median = 0.60g per page view.
Top 10%
Target
Median website

0.55g

45th percentile

Cleaner than 55% of websites

✗ Above the median website

vs Median 8% cleaner ✓
vs Target 10% more
B
Transfer Efficiency
79% efficient
REVIEW
79% efficient
Info::
Transfer efficiency: 79%
An estimated 420 KB (21%) could be eliminated: 0 KB via better compression, 0 KB via modern image formats, 420 KB of unused JavaScript. This wasted data produces 0.12g of unnecessary CO2 per page view.
79% efficient

Total waste: 420 KB (21% of page weight)

Unused JS 420 KB

0.12g unnecessary CO2 per visit

Actual transfer 1997 KB
Theoretical minimum 1576 KB
Potential savings 420 KB (0.12g 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
99% cached
PASS
99% cached
Info::
99% reduction on repeat visits
Returning visitors download only 27 KB (vs 1997 KB first visit). 36 of 37 resources are served from browser cache, saving 0.54g CO2 per repeat visit.
Info::
Repeat visit: 0.01g CO2 (first visit: 0.55g)
First visit
1997 KB
Repeat visit
27 KB

99% reduction on repeat visits

Saving 0.54g CO2 per returning visitor

36 resources served from cache · 1 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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