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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
56
GRADE
D
FIX
3
REVIEW
2
PASS
1
INFO
0
Device:
Mobile Desktop
Checks
6
1 PASS 2 REVIEW 3 FIX
F
CO2 Per Page Load
Action
1.76g CO2 per view
FIX
1.76g CO2 per view
Warning::
1.76g CO2 per page view
This page transfers 6.2 MB, producing an estimated 1.76g of CO2 per visit using the Sustainable Web Design model (v4). Breakdown: data center 0.33g, network 0.30g, end-user device 1.13g.
Got: 1.76g CO2 Expected: < 0.50g (sustainability target)
Info::
At 10,000 monthly views: 211.0 kg CO2/year
With 10,000 page views per month, this page would generate approximately 211.0 kg of CO2 annually — equivalent to charging 26376 smartphones.

1.76g

Carbon Footprint per page view

✗ Above sustainability target (0.50g)

Cleaner than 17% of websites

Sustainable Web Design model v4 · Page size: 6.2 MB

Your site
1.76g
Top 10%
0.20g
Target
0.50g
Median website
0.60g

Energy Breakdown

Data center
0.33g
Network
0.30g
End-user device
1.13g
At 10,000 monthly views: Monthly: 17.6 kg · Annual: 211.0 kg · ≈ 26376 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

F
Carbon Budget
Action
83th percentile
FIX
83th percentile
Warning::
1.76g CO2 — above the median website (0.60g)
Heavier than an estimated 17% of websites. Reducing page weight, optimizing images, and removing unused JavaScript would lower the carbon footprint. See the Performance tab.
Info::
Estimated 83th percentile
Compared to: top 10% = 0.20g, target = 0.50g, median = 0.60g per page view.
Top 10%
Target
Median website

1.76g

83rd percentile

Cleaner than 17% of websites

✗ Above the median website

vs Median 193% more
vs Target 252% more
B
Transfer Efficiency
77% efficient
REVIEW
77% efficient
Info::
Transfer efficiency: 77%
An estimated 1483 KB (23%) could be eliminated: 0 KB via better compression, 0 KB via modern image formats, 1483 KB of unused JavaScript. This wasted data produces 0.41g of unnecessary CO2 per page view.
77% efficient

Total waste: 1483 KB (23% of page weight)

Unused JS 1483 KB

0.41g unnecessary CO2 per visit

Actual transfer 6358 KB
Theoretical minimum 4874 KB
Potential savings 1483 KB (0.41g 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
96% cached
PASS
96% cached
Info::
96% reduction on repeat visits
Returning visitors download only 250 KB (vs 6358 KB first visit). 698 of 808 resources are served from browser cache, saving 1.69g CO2 per repeat visit.
Info::
Repeat visit: 0.07g CO2 (first visit: 1.76g)
First visit
6358 KB
Repeat visit
250 KB

96% reduction on repeat visits

Saving 1.69g CO2 per returning visitor

698 resources served from cache · 110 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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