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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
60
GRADE
D
FIX
2
REVIEW
3
PASS
1
INFO
0
Device:
Mobile Desktop
Checks
6
1 PASS 3 REVIEW 2 FIX
D
Green Hosting
Action
Not green
FIX
Not green
Info::
No confirmed renewable energy commitment detected
Consider providers like Cloudflare, Google Cloud, or Vercel that match 100% of their energy use with renewables.
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 HostingNot Green Hosted
Hosting Snowplow Analytics✗CDN Not identified✗

Based on known provider commitments. Verify at thegreenwebfoundation.org

D
Carbon Budget
Action
54th percentile
FIX
54th percentile
Warning::
0.74g CO2 — above the median website (0.60g)
Heavier than an estimated 46% of websites. Reducing page weight, optimizing images, and removing unused JavaScript would lower the carbon footprint. See the Performance tab.
Info::
Estimated 54th percentile
Compared to: top 10% = 0.20g, target = 0.50g, median = 0.60g per page view.
Top 10%
Target
Median website

0.74g

54th percentile

Cleaner than 46% of websites

✗ Above the median website

vs Median 24% more
vs Target 49% more
B
CO2 Per Page Load
0.74g CO2 per view
REVIEW
0.74g CO2 per view
Info::
0.74g CO2 per page view
This page transfers 2.6 MB, producing an estimated 0.74g of CO2 per visit using the Sustainable Web Design model (v4). Breakdown: data center 0.14g, network 0.13g, end-user device 0.48g.
Got: 0.74g CO2 Expected: < 0.50g (sustainability target)
Info::
At 10,000 monthly views: 89.4 kg CO2/year
With 10,000 page views per month, this page would generate approximately 89.4 kg of CO2 annually — equivalent to charging 11169 smartphones.

0.74g

Carbon Footprint per page view

✗ Above sustainability target (0.50g)

Cleaner than 46% of websites

Sustainable Web Design model v4 · Page size: 2.6 MB

Your site
0.74g
Top 10%
0.20g
Target
0.50g
Median website
0.60g

Energy Breakdown

Data center
0.14g
Network
0.13g
End-user device
0.48g
At 10,000 monthly views: Monthly: 7.4 kg · Annual: 89.4 kg · ≈ 11169 smartphone charges
C
Transfer Efficiency
Action
62% efficient
REVIEW
62% efficient
Warning::
Transfer efficiency: 62%
An estimated 1032 KB (38%) could be eliminated: 0 KB via better compression, 0 KB via modern image formats, 1032 KB of unused JavaScript. This wasted data produces 0.29g of unnecessary CO2 per page view.
62% efficient

Total waste: 1032 KB (38% of page weight)

Unused JS 1032 KB

0.29g unnecessary CO2 per visit

Actual transfer 2692 KB
Theoretical minimum 1660 KB
Potential savings 1032 KB (0.29g 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
97% cached
PASS
97% cached
Info::
97% reduction on repeat visits
Returning visitors download only 86 KB (vs 2692 KB first visit). 137 of 141 resources are served from browser cache, saving 0.72g CO2 per repeat visit.
Info::
Repeat visit: 0.02g CO2 (first visit: 0.74g)
First visit
2692 KB
Repeat visit
86 KB

97% reduction on repeat visits

Saving 0.72g CO2 per returning visitor

137 resources served from cache · 4 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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