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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
54
GRADE
F
FIX
3
REVIEW
2
PASS
1
INFO
0
Device:
Mobile Desktop
Checks
6
1 PASS 2 REVIEW 3 FIX
F
CO2 Per Page Load
Action
1.97g CO2 per view
FIX
1.97g CO2 per view
Warning::
1.97g CO2 per page view
This page transfers 7.0 MB, producing an estimated 1.97g of CO2 per visit using the Sustainable Web Design model (v4). Breakdown: data center 0.37g, network 0.34g, end-user device 1.27g.
Got: 1.97g CO2 Expected: < 0.50g (sustainability target)
Info::
At 10,000 monthly views: 236.6 kg CO2/year
With 10,000 page views per month, this page would generate approximately 236.6 kg of CO2 annually — equivalent to charging 29579 smartphones.

1.97g

Carbon Footprint per page view

✗ Above sustainability target (0.50g)

Cleaner than 11% of websites

Sustainable Web Design model v4 · Page size: 7.0 MB

Your site
1.97g
Top 10%
0.20g
Target
0.50g
Median website
0.60g

Energy Breakdown

Data center
0.37g
Network
0.34g
End-user device
1.27g
At 10,000 monthly views: Monthly: 19.7 kg · Annual: 236.6 kg · ≈ 29579 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
89th percentile
FIX
89th percentile
Warning::
1.97g CO2 — above the median website (0.60g)
Heavier than an estimated 11% of websites. Reducing page weight, optimizing images, and removing unused JavaScript would lower the carbon footprint. See the Performance tab.
Info::
Estimated 89th percentile
Compared to: top 10% = 0.20g, target = 0.50g, median = 0.60g per page view.
Top 10%
Target
Median website

1.97g

89th percentile

Cleaner than 11% of websites

✗ Above the median website

vs Median 229% more
vs Target 294% more
C
Transfer Efficiency
Action
64% efficient
REVIEW
64% efficient
Warning::
Transfer efficiency: 64%
An estimated 2568 KB (36%) could be eliminated: 0 KB via better compression, 0 KB via modern image formats, 2568 KB of unused JavaScript. This wasted data produces 0.71g of unnecessary CO2 per page view.
64% efficient

Total waste: 2568 KB (36% of page weight)

Unused JS 2568 KB

0.71g unnecessary CO2 per visit

Actual transfer 7130 KB
Theoretical minimum 4562 KB
Potential savings 2568 KB (0.71g CO2)

See Deep Analysis sections above for specific optimizations.

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

Green Hosting

No green hosting detected

A+
Repeat Visit Weight
96% cached
PASS
96% cached
Info::
96% reduction on repeat visits
Returning visitors download only 304 KB (vs 7130 KB first visit). 205 of 212 resources are served from browser cache, saving 1.89g CO2 per repeat visit.
Info::
Repeat visit: 0.08g CO2 (first visit: 1.97g)
First visit
7130 KB
Repeat visit
304 KB

96% reduction on repeat visits

Saving 1.89g CO2 per returning visitor

205 resources served from cache · 7 resources re-downloaded

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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