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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::
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 GoDaddy✗CDN Not identified✗

Based on known provider commitments. Verify at thegreenwebfoundation.org

B
CO2 Per Page Load
0.58g CO2 per view
REVIEW
0.58g CO2 per view
Info::
0.58g CO2 per page view
This page transfers 2.0 MB, producing an estimated 0.58g of CO2 per visit using the Sustainable Web Design model (v4). Breakdown: data center 0.11g, network 0.10g, end-user device 0.37g.
Got: 0.58g CO2 Expected: < 0.50g (sustainability target)
Info::
At 10,000 monthly views: 69.4 kg CO2/year
With 10,000 page views per month, this page would generate approximately 69.4 kg of CO2 annually — equivalent to charging 8675 smartphones.

0.58g

Carbon Footprint per page view

✗ Above sustainability target (0.50g)

Cleaner than 53% of websites

Sustainable Web Design model v4 · Page size: 2.0 MB

Your site
0.58g
Top 10%
0.20g
Target
0.50g
Median website
0.60g

Energy Breakdown

Data center
0.11g
Network
0.10g
End-user device
0.37g
At 10,000 monthly views: Monthly: 5.8 kg · Annual: 69.4 kg · ≈ 8675 smartphone charges
B
Carbon Budget
47th percentile
REVIEW
47th percentile
Info::
0.58g CO2 — below the median website (0.60g)
Better than an estimated 53% of websites, but above the sustainability target of 0.50g. Reducing page weight would help reach the target.
Info::
Estimated 47th percentile
Compared to: top 10% = 0.20g, target = 0.50g, median = 0.60g per page view.
Top 10%
Target
Median website

0.58g

47th percentile

Cleaner than 53% of websites

✗ Above the median website

vs Median 4% cleaner ✓
vs Target 16% more
B
Transfer Efficiency
90% efficient
REVIEW
90% efficient
Info::
Transfer efficiency: 90%
An estimated 218 KB (10%) could be eliminated: 0 KB via better compression, 0 KB via modern image formats, 218 KB of unused JavaScript. This wasted data produces 0.06g of unnecessary CO2 per page view.
90% efficient

Total waste: 218 KB (10% of page weight)

Unused JS 218 KB

0.06g unnecessary CO2 per visit

Actual transfer 2091 KB
Theoretical minimum 1872 KB
Potential savings 218 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+
Repeat Visit Weight
97% cached
PASS
97% cached
Info::
97% reduction on repeat visits
Returning visitors download only 62 KB (vs 2091 KB first visit). 32 of 34 resources are served from browser cache, saving 0.56g CO2 per repeat visit.
Info::
Repeat visit: 0.02g CO2 (first visit: 0.58g)
First visit
2091 KB
Repeat visit
62 KB

97% reduction on repeat visits

Saving 0.56g CO2 per returning visitor

32 resources served from cache · 2 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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