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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
82
GRADE
B
FIX
1
REVIEW
1
PASS
4
INFO
0
Checks
6
4 PASS 1 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::
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 HTTPAPI✗CDN Not identified✗

Based on known provider commitments. Verify at thegreenwebfoundation.org

C
Green Hosting
Action
Whether the site is served from green-energy infrastructure
REVIEW

Green Hosting

No green hosting detected

A
CO2 Per Page Load
0.35g CO2 per view
PASS
0.35g CO2 per view
Info::
0.35g CO2 per page view
This page transfers 1.2 MB, producing an estimated 0.35g of CO2 per visit using the Sustainable Web Design model (v4). Breakdown: data center 0.06g, network 0.06g, end-user device 0.22g.
Got: 0.35g CO2 Expected: < 0.50g (sustainability target)
Info::
At 10,000 monthly views: 41.9 kg CO2/year
With 10,000 page views per month, this page would generate approximately 41.9 kg of CO2 annually — equivalent to charging 5231 smartphones.

0.35g

Carbon Footprint per page view

✓ Below sustainability target (0.50g)

Cleaner than 76% of websites

Sustainable Web Design model v4 · Page size: 1.2 MB

Your site
0.35g
Top 10%
0.20g
Target
0.50g
Median website
0.60g

Energy Breakdown

Data center
0.06g
Network
0.06g
End-user device
0.22g
At 10,000 monthly views: Monthly: 3.5 kg · Annual: 41.9 kg · ≈ 5231 smartphone charges
A+
Repeat Visit Weight
93% cached
PASS
93% cached
Info::
93% reduction on repeat visits
Returning visitors download only 85 KB (vs 1261 KB first visit). 159 of 162 resources are served from browser cache, saving 0.33g CO2 per repeat visit.
Info::
Repeat visit: 0.02g CO2 (first visit: 0.35g)
First visit
1261 KB
Repeat visit
85 KB

93% reduction on repeat visits

Saving 0.33g CO2 per returning visitor

159 resources served from cache · 3 resources re-downloaded

A
Carbon Budget
24th percentile
PASS
24th percentile
Info::
0.35g CO2 — below the sustainability target of 0.50g
Cleaner than an estimated 76% of websites analyzed. This page meets the Web Sustainability Guidelines target.
Info::
Estimated 24th percentile
Compared to: top 10% = 0.20g, target = 0.50g, median = 0.60g per page view.
Top 10%
Target
Median website

0.35g

24th percentile

Cleaner than 76% of websites

✓ Below the Web Sustainability Guidelines target

vs Median 42% cleaner ✓
vs Target 30% cleaner ✓
A+
Transfer Efficiency
97% efficient
PASS
97% efficient
Info::
Transfer efficiency: 97%
Only 33 KB of potential savings identified. Your page is well-optimized for size.
97% efficient

Total waste: 33 KB (3% of page weight)

Unused JS 33 KB

0.01g unnecessary CO2 per visit

Actual transfer 1261 KB
Theoretical minimum 1227 KB
Potential savings 33 KB (0.01g 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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