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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
3
REVIEW
2
PASS
1
INFO
0
Device:
Mobile Desktop
Checks
6
1 PASS 2 REVIEW 3 FIX
D
CO2 Per Page Load
Action
0.83g CO2 per view
FIX
0.83g CO2 per view
Info::
0.83g CO2 per page view
This page transfers 2.9 MB, producing an estimated 0.83g of CO2 per visit using the Sustainable Web Design model (v4). Breakdown: data center 0.15g, network 0.14g, end-user device 0.53g.
Got: 0.83g CO2 Expected: < 0.50g (sustainability target)
Info::
At 10,000 monthly views: 99.8 kg CO2/year
With 10,000 page views per month, this page would generate approximately 99.8 kg of CO2 annually — equivalent to charging 12478 smartphones.

0.83g

Carbon Footprint per page view

✗ Above sustainability target (0.50g)

Cleaner than 44% of websites

Sustainable Web Design model v4 · Page size: 2.9 MB

Your site
0.83g
Top 10%
0.20g
Target
0.50g
Median website
0.60g

Energy Breakdown

Data center
0.15g
Network
0.14g
End-user device
0.53g
At 10,000 monthly views: Monthly: 8.3 kg · Annual: 99.8 kg · ≈ 12478 smartphone charges
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
56th percentile
FIX
56th percentile
Warning::
0.83g CO2 — above the median website (0.60g)
Heavier than an estimated 44% of websites. Reducing page weight, optimizing images, and removing unused JavaScript would lower the carbon footprint. See the Performance tab.
Info::
Estimated 56th percentile
Compared to: top 10% = 0.20g, target = 0.50g, median = 0.60g per page view.
Top 10%
Target
Median website

0.83g

56th percentile

Cleaner than 44% of websites

✗ Above the median website

vs Median 39% more
vs Target 66% more
B
Transfer Efficiency
85% efficient
REVIEW
85% efficient
Info::
Transfer efficiency: 85%
An estimated 447 KB (15%) 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.
85% efficient

Total waste: 447 KB (15% of page weight)

Unused JS 447 KB

0.12g unnecessary CO2 per visit

Actual transfer 3008 KB
Theoretical minimum 2560 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
93% cached
PASS
93% cached
Info::
93% reduction on repeat visits
Returning visitors download only 199 KB (vs 3008 KB first visit). 163 of 164 resources are served from browser cache, saving 0.78g CO2 per repeat visit.
Info::
Repeat visit: 0.06g CO2 (first visit: 0.83g)
First visit
3008 KB
Repeat visit
199 KB

93% reduction on repeat visits

Saving 0.78g CO2 per returning visitor

163 resources served from cache · 1 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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