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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
68
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 Next.js✗CDN Not identified✗

Based on known provider commitments. Verify at thegreenwebfoundation.org

D
Carbon Budget
Action
52th percentile
FIX
52th percentile
Warning::
0.69g CO2 — above the median website (0.60g)
Heavier than an estimated 48% of websites. Reducing page weight, optimizing images, and removing unused JavaScript would lower the carbon footprint. See the Performance tab.
Info::
Estimated 52th percentile
Compared to: top 10% = 0.20g, target = 0.50g, median = 0.60g per page view.
Top 10%
Target
Median website

0.69g

52nd percentile

Cleaner than 48% of websites

✗ Above the median website

vs Median 15% more
vs Target 38% more
B
CO2 Per Page Load
0.69g CO2 per view
REVIEW
0.69g CO2 per view
Info::
0.69g CO2 per page view
This page transfers 2.4 MB, producing an estimated 0.69g of CO2 per visit using the Sustainable Web Design model (v4). Breakdown: data center 0.13g, network 0.12g, end-user device 0.44g.
Got: 0.69g CO2 Expected: < 0.50g (sustainability target)
Info::
At 10,000 monthly views: 82.7 kg CO2/year
With 10,000 page views per month, this page would generate approximately 82.7 kg of CO2 annually — equivalent to charging 10335 smartphones.

0.69g

Carbon Footprint per page view

✗ Above sustainability target (0.50g)

Cleaner than 48% of websites

Sustainable Web Design model v4 · Page size: 2.4 MB

Your site
0.69g
Top 10%
0.20g
Target
0.50g
Median website
0.60g

Energy Breakdown

Data center
0.13g
Network
0.12g
End-user device
0.44g
At 10,000 monthly views: Monthly: 6.9 kg · Annual: 82.7 kg · ≈ 10335 smartphone charges
B
Transfer Efficiency
82% efficient
REVIEW
82% efficient
Info::
Transfer efficiency: 82%
An estimated 447 KB (18%) could be eliminated: 0 KB via better compression, 0 KB via modern image formats, 447 KB of unused JavaScript. This wasted data produces 0.12g of unnecessary CO2 per page view.
82% efficient

Total waste: 447 KB (18% of page weight)

Unused JS 447 KB

0.12g unnecessary CO2 per visit

Actual transfer 2491 KB
Theoretical minimum 2043 KB
Potential savings 447 KB (0.12g 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 74 KB (vs 2491 KB first visit). 183 of 186 resources are served from browser cache, saving 0.67g CO2 per repeat visit.
Info::
Repeat visit: 0.02g CO2 (first visit: 0.69g)
First visit
2491 KB
Repeat visit
74 KB

97% reduction on repeat visits

Saving 0.67g CO2 per returning visitor

183 resources served from cache · 3 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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