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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
78
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::
AWS: Renewable energy varies by region; committed to 100% by 2025
Info::
AWS CloudFront: Renewable varies by edge location
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 AWS✗CDN AWS CloudFront✗

AWS: Renewable energy varies by region; committed to 100% by 2025

AWS CloudFront: Renewable varies by edge location

Based on known provider commitments. Verify at thegreenwebfoundation.org

B
Transfer Efficiency
85% efficient
REVIEW
85% efficient
Info::
Transfer efficiency: 85%
An estimated 217 KB (15%) could be eliminated: 0 KB via better compression, 0 KB via modern image formats, 217 KB of unused JavaScript. This wasted data produces 0.06g of unnecessary CO2 per page view.
85% efficient

Total waste: 217 KB (15% of page weight)

Unused JS 217 KB

0.06g unnecessary CO2 per visit

Actual transfer 1409 KB
Theoretical minimum 1192 KB
Potential savings 217 KB (0.06g 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
CO2 Per Page Load
0.39g CO2 per view
PASS
0.39g CO2 per view
Info::
0.39g CO2 per page view
This page transfers 1.4 MB, producing an estimated 0.39g of CO2 per visit using the Sustainable Web Design model (v4). Breakdown: data center 0.07g, network 0.07g, end-user device 0.25g.
Got: 0.39g CO2 Expected: < 0.50g (sustainability target)
Info::
At 10,000 monthly views: 46.8 kg CO2/year
With 10,000 page views per month, this page would generate approximately 46.8 kg of CO2 annually — equivalent to charging 5847 smartphones.

0.39g

Carbon Footprint per page view

✓ Below sustainability target (0.50g)

Cleaner than 72% of websites

Sustainable Web Design model v4 · Page size: 1.4 MB

Your site
0.39g
Top 10%
0.20g
Target
0.50g
Median website
0.60g

Energy Breakdown

Data center
0.07g
Network
0.07g
End-user device
0.25g
At 10,000 monthly views: Monthly: 3.9 kg · Annual: 46.8 kg · ≈ 5847 smartphone charges
A+
Repeat Visit Weight
98% cached
PASS
98% cached
Info::
98% reduction on repeat visits
Returning visitors download only 23 KB (vs 1409 KB first visit). 28 of 29 resources are served from browser cache, saving 0.38g CO2 per repeat visit.
Info::
Repeat visit: 0.01g CO2 (first visit: 0.39g)
First visit
1409 KB
Repeat visit
23 KB

98% reduction on repeat visits

Saving 0.38g CO2 per returning visitor

28 resources served from cache · 1 resources re-downloaded

A
Carbon Budget
28th percentile
PASS
28th percentile
Info::
0.39g CO2 — below the sustainability target of 0.50g
Cleaner than an estimated 72% of websites analyzed. This page meets the Web Sustainability Guidelines target.
Info::
Estimated 28th percentile
Compared to: top 10% = 0.20g, target = 0.50g, median = 0.60g per page view.
Top 10%
Target
Median website

0.39g

28th percentile

Cleaner than 72% of websites

✓ Below the Web Sustainability Guidelines target

vs Median 35% cleaner ✓
vs Target 22% cleaner ✓
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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