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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
59
GRADE
D
FIX
3
REVIEW
1
PASS
2
INFO
0
Checks
6
2 PASS 1 REVIEW 3 FIX
F
CO2 Per Page Load
Action
2.31g CO2 per view
FIX
2.31g CO2 per view
Critical::
2.31g CO2 per page view
This page transfers 8.1 MB, producing an estimated 2.31g of CO2 per visit using the Sustainable Web Design model (v4). Breakdown: data center 0.43g, network 0.40g, end-user device 1.48g.
Got: 2.31g CO2 Expected: < 0.50g (sustainability target)
Info::
At 10,000 monthly views: 276.8 kg CO2/year
With 10,000 page views per month, this page would generate approximately 276.8 kg of CO2 annually — equivalent to charging 34602 smartphones.

2.31g

Carbon Footprint per page view

Above sustainability target (0.50g)

Cleaner than 5% of websites

Sustainable Web Design model v4 · Page size: 8.1 MB

Your site
2.31g
Top 10%
0.20g
Target
0.50g
Median website
0.60g

Energy Breakdown

Data center
0.43g
Network
0.40g
End-user device
1.48g
At 10,000 monthly views: Monthly: 23.1 kg · Annual: 276.8 kg · ≈ 34602 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
95th percentile
FIX
95th percentile
Warning::
2.31g CO2 — above the median website (0.60g)
Heavier than an estimated 5% of websites. Reducing page weight, optimizing images, and removing unused JavaScript would lower the carbon footprint. See the Performance tab.
Info::
Estimated 95th percentile
Compared to: top 10% = 0.20g, target = 0.50g, median = 0.60g per page view.
Top 10%
Target
Median website

2.31g

95th percentile

Cleaner than 5% of websites

Above the median website

vs Median 284% more
vs Target 361% 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
100% cached
PASS
100% cached
Info::
100% reduction on repeat visits
Returning visitors download only 21 KB (vs 8341 KB first visit). 171 of 172 resources are served from browser cache, saving 2.30g CO2 per repeat visit.
Info::
Repeat visit: 0.01g CO2 (first visit: 2.31g)
First visit
8341 KB
Repeat visit
21 KB

100% reduction on repeat visits

Saving 2.30g CO2 per returning visitor

171 resources served from cache · 1 resources re-downloaded

A+
Transfer Efficiency
97% efficient
PASS
97% efficient
Info::
Transfer efficiency: 97%
Only 236 KB of potential savings identified. Your page is well-optimized for size.
97% efficient

Total waste: 236 KB (3% of page weight)

Unused JS 236 KB

0.07g unnecessary CO2 per visit

Actual transfer 8341 KB
Theoretical minimum 8104 KB
Potential savings 236 KB (0.07g 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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