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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
1
REVIEW
2
PASS
3
INFO
0
Device:
Mobile Desktop
Checks
6
3 PASS 2 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 IIS✗CDN Not identified✗

Based on known provider commitments. Verify at thegreenwebfoundation.org

B
Carbon Budget
34th percentile
REVIEW
34th percentile
Info::
0.44g CO2 — below the sustainability target of 0.50g
Cleaner than an estimated 66% of websites analyzed. This page meets the Web Sustainability Guidelines target.
Info::
Estimated 34th percentile
Compared to: top 10% = 0.20g, target = 0.50g, median = 0.60g per page view.
Top 10%
Target
Median website

0.44g

34th percentile

Cleaner than 66% of websites

✓ Below the Web Sustainability Guidelines target

vs Median 26% cleaner ✓
vs Target 12% cleaner ✓
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
0.44g CO2 per view
PASS
0.44g CO2 per view
Info::
0.44g CO2 per page view
This page transfers 1.6 MB, producing an estimated 0.44g of CO2 per visit using the Sustainable Web Design model (v4). Breakdown: data center 0.08g, network 0.08g, end-user device 0.28g.
Got: 0.44g CO2 Expected: < 0.50g (sustainability target)
Info::
At 10,000 monthly views: 52.9 kg CO2/year
With 10,000 page views per month, this page would generate approximately 52.9 kg of CO2 annually — equivalent to charging 6615 smartphones.

0.44g

Carbon Footprint per page view

✓ Below sustainability target (0.50g)

Cleaner than 66% of websites

Sustainable Web Design model v4 · Page size: 1.6 MB

Your site
0.44g
Top 10%
0.20g
Target
0.50g
Median website
0.60g

Energy Breakdown

Data center
0.08g
Network
0.08g
End-user device
0.28g
At 10,000 monthly views: Monthly: 4.4 kg · Annual: 52.9 kg · ≈ 6615 smartphone charges
A+
Repeat Visit Weight
97% cached
PASS
97% cached
Info::
97% reduction on repeat visits
Returning visitors download only 53 KB (vs 1594 KB first visit). 56 of 57 resources are served from browser cache, saving 0.43g CO2 per repeat visit.
Info::
Repeat visit: 0.01g CO2 (first visit: 0.44g)
First visit
1594 KB
Repeat visit
53 KB

97% reduction on repeat visits

Saving 0.43g CO2 per returning visitor

56 resources served from cache · 1 resources re-downloaded

A+
Transfer Efficiency
91% efficient
PASS
91% efficient
Info::
Transfer efficiency: 91%
Only 136 KB of potential savings identified. Your page is well-optimized for size.
91% efficient

Total waste: 136 KB (9% of page weight)

Unused JS 136 KB

0.04g unnecessary CO2 per visit

Actual transfer 1594 KB
Theoretical minimum 1458 KB
Potential savings 136 KB (0.04g 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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