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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
64
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 Amazon Web Services✗CDN Not identified✗

Based on known provider commitments. Verify at thegreenwebfoundation.org

D
Carbon Budget
Action
55th percentile
FIX
55th percentile
Warning::
0.78g CO2 — above the median website (0.60g)
Heavier than an estimated 45% of websites. Reducing page weight, optimizing images, and removing unused JavaScript would lower the carbon footprint. See the Performance tab.
Info::
Estimated 55th percentile
Compared to: top 10% = 0.20g, target = 0.50g, median = 0.60g per page view.
Top 10%
Target
Median website

0.78g

55th percentile

Cleaner than 45% of websites

✗ Above the median website

vs Median 30% more
vs Target 55% more
B
CO2 Per Page Load
0.78g CO2 per view
REVIEW
0.78g CO2 per view
Info::
0.78g CO2 per page view
This page transfers 2.7 MB, producing an estimated 0.78g of CO2 per visit using the Sustainable Web Design model (v4). Breakdown: data center 0.14g, network 0.13g, end-user device 0.50g.
Got: 0.78g CO2 Expected: < 0.50g (sustainability target)
Info::
At 10,000 monthly views: 93.3 kg CO2/year
With 10,000 page views per month, this page would generate approximately 93.3 kg of CO2 annually — equivalent to charging 11660 smartphones.

0.78g

Carbon Footprint per page view

✗ Above sustainability target (0.50g)

Cleaner than 45% of websites

Sustainable Web Design model v4 · Page size: 2.7 MB

Your site
0.78g
Top 10%
0.20g
Target
0.50g
Median website
0.60g

Energy Breakdown

Data center
0.14g
Network
0.13g
End-user device
0.50g
At 10,000 monthly views: Monthly: 7.8 kg · Annual: 93.3 kg · ≈ 11660 smartphone charges
C
Transfer Efficiency
Action
66% efficient
REVIEW
66% efficient
Warning::
Transfer efficiency: 66%
An estimated 954 KB (34%) could be eliminated: 0 KB via better compression, 0 KB via modern image formats, 954 KB of unused JavaScript. This wasted data produces 0.26g of unnecessary CO2 per page view.
66% efficient

Total waste: 954 KB (34% of page weight)

Unused JS 954 KB

0.26g unnecessary CO2 per visit

Actual transfer 2810 KB
Theoretical minimum 1856 KB
Potential savings 954 KB (0.26g 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
95% cached
PASS
95% cached
Info::
95% reduction on repeat visits
Returning visitors download only 141 KB (vs 2810 KB first visit). 156 of 158 resources are served from browser cache, saving 0.74g CO2 per repeat visit.
Info::
Repeat visit: 0.04g CO2 (first visit: 0.78g)
First visit
2810 KB
Repeat visit
141 KB

95% reduction on repeat visits

Saving 0.74g CO2 per returning visitor

156 resources served from cache · 2 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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