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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
4
REVIEW
1
PASS
1
INFO
0
Device:
Mobile Desktop
Checks
6
1 PASS 1 REVIEW 4 FIX
D
CO2 Per Page Load
Action
1.39g CO2 per view
FIX
1.39g CO2 per view
Warning::
1.39g CO2 per page view
This page transfers 4.9 MB, producing an estimated 1.39g of CO2 per visit using the Sustainable Web Design model (v4). Breakdown: data center 0.26g, network 0.24g, end-user device 0.89g.
Got: 1.39g CO2 Expected: < 0.50g (sustainability target)
Info::
At 10,000 monthly views: 166.8 kg CO2/year
With 10,000 page views per month, this page would generate approximately 166.8 kg of CO2 annually — equivalent to charging 20844 smartphones.

1.39g

Carbon Footprint per page view

✗ Above sustainability target (0.50g)

Cleaner than 28% of websites

Sustainable Web Design model v4 · Page size: 4.9 MB

Your site
1.39g
Top 10%
0.20g
Target
0.50g
Median website
0.60g

Energy Breakdown

Data center
0.26g
Network
0.24g
End-user device
0.89g
At 10,000 monthly views: Monthly: 13.9 kg · Annual: 166.8 kg · ≈ 20844 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
72th percentile
FIX
72th percentile
Warning::
1.39g CO2 — above the median website (0.60g)
Heavier than an estimated 28% of websites. Reducing page weight, optimizing images, and removing unused JavaScript would lower the carbon footprint. See the Performance tab.
Info::
Estimated 72th percentile
Compared to: top 10% = 0.20g, target = 0.50g, median = 0.60g per page view.
Top 10%
Target
Median website

1.39g

72nd percentile

Cleaner than 28% of websites

✗ Above the median website

vs Median 132% more
vs Target 178% more
D
Transfer Efficiency
Action
54% efficient
FIX
54% efficient
Warning::
Transfer efficiency: 54%
An estimated 2327 KB (46%) could be eliminated: 0 KB via better compression, 0 KB via modern image formats, 2327 KB of unused JavaScript. This wasted data produces 0.64g of unnecessary CO2 per page view.
54% efficient

Total waste: 2327 KB (46% of page weight)

Unused JS 2327 KB

0.64g unnecessary CO2 per visit

Actual transfer 5024 KB
Theoretical minimum 2696 KB
Potential savings 2327 KB (0.64g 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
99% cached
PASS
99% cached
Info::
99% reduction on repeat visits
Returning visitors download only 57 KB (vs 5024 KB first visit). 221 of 226 resources are served from browser cache, saving 1.37g CO2 per repeat visit.
Info::
Repeat visit: 0.02g CO2 (first visit: 1.39g)
First visit
5024 KB
Repeat visit
57 KB

99% reduction on repeat visits

Saving 1.37g CO2 per returning visitor

221 resources served from cache · 5 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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