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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
Checks
6
2 PASS 1 REVIEW 3 FIX
D
CO2 Per Page Load
Action
1.48g CO2 per view
FIX
1.48g CO2 per view
Warning::
1.48g CO2 per page view
This page transfers 5.2 MB, producing an estimated 1.48g of CO2 per visit using the Sustainable Web Design model (v4). Breakdown: data center 0.27g, network 0.26g, end-user device 0.95g.
Got: 1.48g CO2 Expected: < 0.50g (sustainability target)
Info::
At 10,000 monthly views: 178.1 kg CO2/year
With 10,000 page views per month, this page would generate approximately 178.1 kg of CO2 annually — equivalent to charging 22259 smartphones.

1.48g

Carbon Footprint per page view

Above sustainability target (0.50g)

Cleaner than 25% of websites

Sustainable Web Design model v4 · Page size: 5.2 MB

Your site
1.48g
Top 10%
0.20g
Target
0.50g
Median website
0.60g

Energy Breakdown

Data center
0.27g
Network
0.26g
End-user device
0.95g
At 10,000 monthly views: Monthly: 14.8 kg · Annual: 178.1 kg · ≈ 22259 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 identifiedCDN Not identified

Based on known provider commitments. Verify at thegreenwebfoundation.org

F
Carbon Budget
Action
75th percentile
FIX
75th percentile
Warning::
1.48g CO2 — above the median website (0.60g)
Heavier than an estimated 25% of websites. Reducing page weight, optimizing images, and removing unused JavaScript would lower the carbon footprint. See the Performance tab.
Info::
Estimated 75th percentile
Compared to: top 10% = 0.20g, target = 0.50g, median = 0.60g per page view.
Top 10%
Target
Median website

1.48g

75th percentile

Cleaner than 25% of websites

Above the median website

vs Median 147% more
vs Target 197% 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
99% cached
PASS
99% cached
Info::
99% reduction on repeat visits
Returning visitors download only 49 KB (vs 5365 KB first visit). 140 of 142 resources are served from browser cache, saving 1.47g CO2 per repeat visit.
Info::
Repeat visit: 0.01g CO2 (first visit: 1.48g)
First visit
5365 KB
Repeat visit
49 KB

99% reduction on repeat visits

Saving 1.47g CO2 per returning visitor

140 resources served from cache · 2 resources re-downloaded

A+
Transfer Efficiency
98% efficient
PASS
98% efficient
Info::
Transfer efficiency: 98%
Only 117 KB of potential savings identified. Your page is well-optimized for size.
98% efficient

Total waste: 117 KB (2% of page weight)

Unused JS 117 KB

0.03g unnecessary CO2 per visit

Actual transfer 5365 KB
Theoretical minimum 5248 KB
Potential savings 117 KB (0.03g 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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