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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
56
GRADE
D
FIX
3
REVIEW
2
PASS
1
INFO
0
Device:
Mobile Desktop
Checks
6
1 PASS 2 REVIEW 3 FIX
D
CO2 Per Page Load
Action
0.97g CO2 per view
FIX
0.97g CO2 per view
Info::
0.97g CO2 per page view
This page transfers 3.4 MB, producing an estimated 0.97g of CO2 per visit using the Sustainable Web Design model (v4). Breakdown: data center 0.18g, network 0.17g, end-user device 0.62g.
Got: 0.97g CO2 Expected: < 0.50g (sustainability target)
Info::
At 10,000 monthly views: 116.5 kg CO2/year
With 10,000 page views per month, this page would generate approximately 116.5 kg of CO2 annually — equivalent to charging 14559 smartphones.

0.97g

Carbon Footprint per page view

✗ Above sustainability target (0.50g)

Cleaner than 40% of websites

Sustainable Web Design model v4 · Page size: 3.4 MB

Your site
0.97g
Top 10%
0.20g
Target
0.50g
Median website
0.60g

Energy Breakdown

Data center
0.18g
Network
0.17g
End-user device
0.62g
At 10,000 monthly views: Monthly: 9.7 kg · Annual: 116.5 kg · ≈ 14559 smartphone charges
D
Green Hosting
Action
Unknown
FIX
Unknown
Info::
Hosting provider could not be identified
Without knowing the provider, we cannot determine their energy sourcing. Check with your hosting provider about their renewable energy commitments.
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 HostingUnable to Determine
Hosting Not identified✗CDN Not identified✗

Based on known provider commitments. Verify at thegreenwebfoundation.org

D
Carbon Budget
Action
60th percentile
FIX
60th percentile
Warning::
0.97g CO2 — above the median website (0.60g)
Heavier than an estimated 40% of websites. Reducing page weight, optimizing images, and removing unused JavaScript would lower the carbon footprint. See the Performance tab.
Info::
Estimated 60th percentile
Compared to: top 10% = 0.20g, target = 0.50g, median = 0.60g per page view.
Top 10%
Target
Median website

0.97g

60th percentile

Cleaner than 40% of websites

✗ Above the median website

vs Median 62% more
vs Target 94% more
B
Transfer Efficiency
86% efficient
REVIEW
86% efficient
Info::
Transfer efficiency: 86%
An estimated 477 KB (14%) could be eliminated: 0 KB via better compression, 0 KB via modern image formats, 477 KB of unused JavaScript. This wasted data produces 0.13g of unnecessary CO2 per page view.
86% efficient

Total waste: 477 KB (14% of page weight)

Unused JS 477 KB

0.13g unnecessary CO2 per visit

Actual transfer 3509 KB
Theoretical minimum 3032 KB
Potential savings 477 KB (0.13g 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
98% cached
PASS
98% cached
Info::
98% reduction on repeat visits
Returning visitors download only 82 KB (vs 3509 KB first visit). 122 of 123 resources are served from browser cache, saving 0.95g CO2 per repeat visit.
Info::
Repeat visit: 0.02g CO2 (first visit: 0.97g)
First visit
3509 KB
Repeat visit
82 KB

98% reduction on repeat visits

Saving 0.95g CO2 per returning visitor

122 resources served from cache · 1 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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