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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
66
GRADE
D
FIX
3
REVIEW
1
PASS
2
INFO
0
Device:
Mobile Desktop
Checks
6
2 PASS 1 REVIEW 3 FIX
D
CO2 Per Page Load
Action
1.37g CO2 per view
FIX
1.37g CO2 per view
Warning::
1.37g CO2 per page view
This page transfers 4.8 MB, producing an estimated 1.37g of CO2 per visit using the Sustainable Web Design model (v4). Breakdown: data center 0.25g, network 0.24g, end-user device 0.88g.
Got: 1.37g CO2 Expected: < 0.50g (sustainability target)
Info::
At 10,000 monthly views: 164.5 kg CO2/year
With 10,000 page views per month, this page would generate approximately 164.5 kg of CO2 annually — equivalent to charging 20557 smartphones.

1.37g

Carbon Footprint per page view

✗ Above sustainability target (0.50g)

Cleaner than 28% of websites

Sustainable Web Design model v4 · Page size: 4.8 MB

Your site
1.37g
Top 10%
0.20g
Target
0.50g
Median website
0.60g

Energy Breakdown

Data center
0.25g
Network
0.24g
End-user device
0.88g
At 10,000 monthly views: Monthly: 13.7 kg · Annual: 164.5 kg · ≈ 20557 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

F
Carbon Budget
Action
72th percentile
FIX
72th percentile
Warning::
1.37g CO2 — above the median website (0.60g)
Heavier than an estimated 28% of websites. Reducing page weight, optimizing images, and removing unused JavaScript would lower the carbon footprint. See the Performance tab.
Info::
Estimated 72th percentile
Compared to: top 10% = 0.20g, target = 0.50g, median = 0.60g per page view.
Top 10%
Target
Median website

1.37g

72nd percentile

Cleaner than 28% of websites

✗ Above the median website

vs Median 128% more
vs Target 174% more
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 132 KB (vs 4955 KB first visit). 80 of 85 resources are served from browser cache, saving 1.33g CO2 per repeat visit.
Info::
Repeat visit: 0.04g CO2 (first visit: 1.37g)
First visit
4955 KB
Repeat visit
132 KB

97% reduction on repeat visits

Saving 1.33g CO2 per returning visitor

80 resources served from cache · 5 resources re-downloaded

A+
Transfer Efficiency
96% efficient
PASS
96% efficient
Info::
Transfer efficiency: 96%
Only 185 KB of potential savings identified. Your page is well-optimized for size.
96% efficient

Total waste: 185 KB (4% of page weight)

Unused JS 185 KB

0.05g unnecessary CO2 per visit

Actual transfer 4955 KB
Theoretical minimum 4769 KB
Potential savings 185 KB (0.05g 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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