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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
Checks
6
2 PASS 1 REVIEW 3 FIX
D
CO2 Per Page Load
Action
1.49g CO2 per view
FIX
1.49g CO2 per view
Warning::
1.49g CO2 per page view
This page transfers 5.3 MB, producing an estimated 1.49g of CO2 per visit using the Sustainable Web Design model (v4). Breakdown: data center 0.28g, network 0.26g, end-user device 0.96g.
Got: 1.49g CO2 Expected: < 0.50g (sustainability target)
Info::
At 10,000 monthly views: 178.7 kg CO2/year
With 10,000 page views per month, this page would generate approximately 178.7 kg of CO2 annually — equivalent to charging 22341 smartphones.

1.49g

Carbon Footprint per page view

Above sustainability target (0.50g)

Cleaner than 25% of websites

Sustainable Web Design model v4 · Page size: 5.3 MB

Your site
1.49g
Top 10%
0.20g
Target
0.50g
Median website
0.60g

Energy Breakdown

Data center
0.28g
Network
0.26g
End-user device
0.96g
At 10,000 monthly views: Monthly: 14.9 kg · Annual: 178.7 kg · ≈ 22341 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::
1.49g 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

1.49g

75th percentile

Cleaner than 25% of websites

Above the median website

vs Median 148% more
vs Target 198% 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 26 KB (vs 5385 KB first visit). 54 of 55 resources are served from browser cache, saving 1.48g CO2 per repeat visit.
Info::
Repeat visit: 0.01g CO2 (first visit: 1.49g)
First visit
5385 KB
Repeat visit
26 KB

100% reduction on repeat visits

Saving 1.48g CO2 per returning visitor

54 resources served from cache · 1 resources re-downloaded

A+
Transfer Efficiency
92% efficient
PASS
92% efficient
Info::
Transfer efficiency: 92%
Only 432 KB of potential savings identified. Your page is well-optimized for size.
92% efficient

Total waste: 432 KB (8% of page weight)

Unused JS 432 KB

0.12g unnecessary CO2 per visit

Actual transfer 5385 KB
Theoretical minimum 4953 KB
Potential savings 432 KB (0.12g 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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