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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
1.44g CO2 per view
FIX
1.44g CO2 per view
Warning::
1.44g CO2 per page view
This page transfers 5.1 MB, producing an estimated 1.44g of CO2 per visit using the Sustainable Web Design model (v4). Breakdown: data center 0.27g, network 0.25g, end-user device 0.92g.
Got: 1.44g CO2 Expected: < 0.50g (sustainability target)
Info::
At 10,000 monthly views: 172.7 kg CO2/year
With 10,000 page views per month, this page would generate approximately 172.7 kg of CO2 annually — equivalent to charging 21583 smartphones.

1.44g

Carbon Footprint per page view

✗ Above sustainability target (0.50g)

Cleaner than 27% of websites

Sustainable Web Design model v4 · Page size: 5.1 MB

Your site
1.44g
Top 10%
0.20g
Target
0.50g
Median website
0.60g

Energy Breakdown

Data center
0.27g
Network
0.25g
End-user device
0.92g
At 10,000 monthly views: Monthly: 14.4 kg · Annual: 172.7 kg · ≈ 21583 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
73th percentile
FIX
73th percentile
Warning::
1.44g CO2 — above the median website (0.60g)
Heavier than an estimated 27% of websites. Reducing page weight, optimizing images, and removing unused JavaScript would lower the carbon footprint. See the Performance tab.
Info::
Estimated 73th percentile
Compared to: top 10% = 0.20g, target = 0.50g, median = 0.60g per page view.
Top 10%
Target
Median website

1.44g

73rd percentile

Cleaner than 27% of websites

✗ Above the median website

vs Median 140% more
vs Target 188% 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 32 KB (vs 5202 KB first visit). 37 of 38 resources are served from browser cache, saving 1.43g CO2 per repeat visit.
Info::
Repeat visit: 0.01g CO2 (first visit: 1.44g)
First visit
5202 KB
Repeat visit
32 KB

99% reduction on repeat visits

Saving 1.43g CO2 per returning visitor

37 resources served from cache · 1 resources re-downloaded

A+
Transfer Efficiency
96% efficient
PASS
96% efficient
Info::
Transfer efficiency: 96%
Only 183 KB of potential savings identified. Your page is well-optimized for size.
96% efficient

Total waste: 183 KB (4% of page weight)

Unused JS 183 KB

0.05g unnecessary CO2 per visit

Actual transfer 5202 KB
Theoretical minimum 5018 KB
Potential savings 183 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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