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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
2
REVIEW
2
PASS
2
INFO
0
Device:
Mobile Desktop
Checks
6
2 PASS 2 REVIEW 2 FIX
D
CO2 Per Page Load
Action
1.25g CO2 per view
FIX
1.25g CO2 per view
Warning::
1.25g CO2 per page view
This page transfers 5.3 MB, producing an estimated 1.25g of CO2 per visit using the Sustainable Web Design model (v4). Breakdown: data center 0.03g, network 0.26g, end-user device 0.96g.
Got: 1.25g CO2 Expected: < 0.50g (sustainability target)
Info::
At 10,000 monthly views: 149.8 kg CO2/year
With 10,000 page views per month, this page would generate approximately 149.8 kg of CO2 annually — equivalent to charging 18724 smartphones.
Info::
Green hosting reduces data center emissions

1.25g

Carbon Footprint per page view

✗ Above sustainability target (0.50g)

Cleaner than 32% of websites

Sustainable Web Design model v4 · Page size: 5.3 MB

Your site
1.25g
Top 10%
0.20g
Target
0.50g
Median website
0.60g

Energy Breakdown

Data center
0.03g
Network
0.26g
End-user device
0.96g
At 10,000 monthly views: Monthly: 12.5 kg · Annual: 149.8 kg · ≈ 18724 smartphone charges
D
Carbon Budget
Action
68th percentile
FIX
68th percentile
Warning::
1.25g CO2 — above the median website (0.60g)
Heavier than an estimated 32% of websites. Reducing page weight, optimizing images, and removing unused JavaScript would lower the carbon footprint. See the Performance tab.
Info::
Estimated 68th percentile
Compared to: top 10% = 0.20g, target = 0.50g, median = 0.60g per page view.
Top 10%
Target
Median website

1.25g

68th percentile

Cleaner than 32% of websites

✗ Above the median website

vs Median 108% more
vs Target 150% more
B
Green Hosting
Green (hosting)
REVIEW
Green (hosting)
Info::
Zengenti uses renewable energy
Info::
Zengenti: Verified by the Green Web Foundation
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 Hosting✓ Green Hosted
Hosting Zengenti✓CDN Not identified✗

Zengenti: Verified by the Green Web Foundation

Based on known provider commitments. Verify at thegreenwebfoundation.org

B
Transfer Efficiency
79% efficient
REVIEW
79% efficient
Info::
Transfer efficiency: 79%
An estimated 1143 KB (21%) could be eliminated: 0 KB via better compression, 0 KB via modern image formats, 1143 KB of unused JavaScript. This wasted data produces 0.26g of unnecessary CO2 per page view.
79% efficient

Total waste: 1143 KB (21% of page weight)

Unused JS 1143 KB

0.26g unnecessary CO2 per visit

Actual transfer 5400 KB
Theoretical minimum 4256 KB
Potential savings 1143 KB (0.26g CO2)

See Deep Analysis sections above for specific optimizations.

A+
Repeat Visit Weight
99% cached
PASS
99% cached
Info::
99% reduction on repeat visits
Returning visitors download only 78 KB (vs 5400 KB first visit). 101 of 103 resources are served from browser cache, saving 1.23g CO2 per repeat visit.
Info::
Repeat visit: 0.02g CO2 (first visit: 1.25g)
First visit
5400 KB
Repeat visit
78 KB

99% reduction on repeat visits

Saving 1.23g CO2 per returning visitor

101 resources served from cache · 2 resources re-downloaded

A+
Green Hosting
Whether the site is served from green-energy infrastructure
PASS

Green Hosting

This site is hosted on green energy infrastructure

Provider: Zengenti

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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