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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
2
PASS
1
INFO
0
Device:
Mobile Desktop
Checks
6
1 PASS 2 REVIEW 3 FIX
D
CO2 Per Page Load
Action
1.25g CO2 per view
FIX
1.25g CO2 per view
Warning::
1.25g CO2 per page view
This page transfers 4.4 MB, producing an estimated 1.25g of CO2 per visit using the Sustainable Web Design model (v4). Breakdown: data center 0.23g, network 0.22g, end-user device 0.80g.
Got: 1.25g CO2 Expected: < 0.50g (sustainability target)
Info::
At 10,000 monthly views: 149.7 kg CO2/year
With 10,000 page views per month, this page would generate approximately 149.7 kg of CO2 annually — equivalent to charging 18713 smartphones.

1.25g

Carbon Footprint per page view

✗ Above sustainability target (0.50g)

Cleaner than 32% of websites

Sustainable Web Design model v4 · Page size: 4.4 MB

Your site
1.25g
Top 10%
0.20g
Target
0.50g
Median website
0.60g

Energy Breakdown

Data center
0.23g
Network
0.22g
End-user device
0.80g
At 10,000 monthly views: Monthly: 12.5 kg · Annual: 149.7 kg · ≈ 18713 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
68th percentile
FIX
68th percentile
Warning::
1.25g CO2 — above the median website (0.60g)
Heavier than an estimated 32% of websites. Reducing page weight, optimizing images, and removing unused JavaScript would lower the carbon footprint. See the Performance tab.
Info::
Estimated 68th percentile
Compared to: top 10% = 0.20g, target = 0.50g, median = 0.60g per page view.
Top 10%
Target
Median website

1.25g

68th percentile

Cleaner than 32% of websites

✗ Above the median website

vs Median 108% more
vs Target 150% more
B
Repeat Visit Weight
69% cached
REVIEW
69% cached
Info::
69% reduction on repeat visits
Returning visitors download only 1410 KB (vs 4510 KB first visit). 63 of 65 resources are served from browser cache, saving 0.86g CO2 per repeat visit.
Info::
Repeat visit: 0.39g CO2 (first visit: 1.25g)
First visit
4510 KB
Repeat visit
1410 KB

69% reduction on repeat visits

Saving 0.86g CO2 per returning visitor

63 resources served from cache · 2 resources re-downloaded

C
Green Hosting
Action
Whether the site is served from green-energy infrastructure
REVIEW

Green Hosting

No green hosting detected

A+
Transfer Efficiency
94% efficient
PASS
94% efficient
Info::
Transfer efficiency: 94%
Only 279 KB of potential savings identified. Your page is well-optimized for size.
94% efficient

Total waste: 279 KB (6% of page weight)

Unused JS 279 KB

0.08g unnecessary CO2 per visit

Actual transfer 4510 KB
Theoretical minimum 4230 KB
Potential savings 279 KB (0.08g 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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