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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
58
GRADE
D
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
1.56g CO2 per view
FIX
1.56g CO2 per view
Warning::
1.56g CO2 per page view
This page transfers 5.5 MB, producing an estimated 1.56g of CO2 per visit using the Sustainable Web Design model (v4). Breakdown: data center 0.29g, network 0.27g, end-user device 1.00g.
Got: 1.56g CO2 Expected: < 0.50g (sustainability target)
Info::
At 10,000 monthly views: 187.3 kg CO2/year
With 10,000 page views per month, this page would generate approximately 187.3 kg of CO2 annually — equivalent to charging 23416 smartphones.

1.56g

Carbon Footprint per page view

✗ Above sustainability target (0.50g)

Cleaner than 23% of websites

Sustainable Web Design model v4 · Page size: 5.5 MB

Your site
1.56g
Top 10%
0.20g
Target
0.50g
Median website
0.60g

Energy Breakdown

Data center
0.29g
Network
0.27g
End-user device
1.00g
At 10,000 monthly views: Monthly: 15.6 kg · Annual: 187.3 kg · ≈ 23416 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
77th percentile
FIX
77th percentile
Warning::
1.56g CO2 — above the median website (0.60g)
Heavier than an estimated 23% of websites. Reducing page weight, optimizing images, and removing unused JavaScript would lower the carbon footprint. See the Performance tab.
Info::
Estimated 77th percentile
Compared to: top 10% = 0.20g, target = 0.50g, median = 0.60g per page view.
Top 10%
Target
Median website

1.56g

77th percentile

Cleaner than 23% of websites

✗ Above the median website

vs Median 160% more
vs Target 212% more
B
Transfer Efficiency
84% efficient
REVIEW
84% efficient
Info::
Transfer efficiency: 84%
An estimated 888 KB (16%) could be eliminated: 0 KB via better compression, 0 KB via modern image formats, 888 KB of unused JavaScript. This wasted data produces 0.25g of unnecessary CO2 per page view.
84% efficient

Total waste: 888 KB (16% of page weight)

Unused JS 888 KB

0.25g unnecessary CO2 per visit

Actual transfer 5644 KB
Theoretical minimum 4756 KB
Potential savings 888 KB (0.25g 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 227 KB (vs 5644 KB first visit). 380 of 402 resources are served from browser cache, saving 1.50g CO2 per repeat visit.
Info::
Repeat visit: 0.06g CO2 (first visit: 1.56g)
First visit
5644 KB
Repeat visit
227 KB

96% reduction on repeat visits

Saving 1.50g CO2 per returning visitor

380 resources served from cache · 22 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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