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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
70
GRADE
C
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
1.14g CO2 per view
FIX
1.14g CO2 per view
Warning::
1.14g CO2 per page view
This page transfers 4.0 MB, producing an estimated 1.14g of CO2 per visit using the Sustainable Web Design model (v4). Breakdown: data center 0.21g, network 0.20g, end-user device 0.73g.
Got: 1.14g CO2 Expected: < 0.50g (sustainability target)
Info::
At 10,000 monthly views: 137.4 kg CO2/year
With 10,000 page views per month, this page would generate approximately 137.4 kg of CO2 annually — equivalent to charging 17169 smartphones.

1.14g

Carbon Footprint per page view

✗ Above sustainability target (0.50g)

Cleaner than 35% of websites

Sustainable Web Design model v4 · Page size: 4.0 MB

Your site
1.14g
Top 10%
0.20g
Target
0.50g
Median website
0.60g

Energy Breakdown

Data center
0.21g
Network
0.20g
End-user device
0.73g
At 10,000 monthly views: Monthly: 11.4 kg · Annual: 137.4 kg · ≈ 17169 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
65th percentile
FIX
65th percentile
Warning::
1.14g CO2 — above the median website (0.60g)
Heavier than an estimated 35% of websites. Reducing page weight, optimizing images, and removing unused JavaScript would lower the carbon footprint. See the Performance tab.
Info::
Estimated 65th percentile
Compared to: top 10% = 0.20g, target = 0.50g, median = 0.60g per page view.
Top 10%
Target
Median website

1.14g

65th percentile

Cleaner than 35% of websites

✗ Above the median website

vs Median 91% more
vs Target 129% 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
98% cached
PASS
98% cached
Info::
98% reduction on repeat visits
Returning visitors download only 79 KB (vs 4138 KB first visit). 113 of 114 resources are served from browser cache, saving 1.12g CO2 per repeat visit.
Info::
Repeat visit: 0.02g CO2 (first visit: 1.14g)
First visit
4138 KB
Repeat visit
79 KB

98% reduction on repeat visits

Saving 1.12g CO2 per returning visitor

113 resources served from cache · 1 resources re-downloaded

A+
Transfer Efficiency
91% efficient
PASS
91% efficient
Info::
Transfer efficiency: 91%
Only 379 KB of potential savings identified. Your page is well-optimized for size.
91% efficient

Total waste: 379 KB (9% of page weight)

Unused JS 379 KB

0.10g unnecessary CO2 per visit

Actual transfer 4138 KB
Theoretical minimum 3759 KB
Potential savings 379 KB (0.10g 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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