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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
D
CO2 Per Page Load
Action
1.25g CO2 per view
FIX
1.25g CO2 per view
Warning::
1.25g CO2 per page view
This page transfers 4.4 MB, producing an estimated 1.25g of CO2 per visit using the Sustainable Web Design model (v4). Breakdown: data center 0.23g, network 0.22g, end-user device 0.80g.
Got: 1.25g CO2 Expected: < 0.50g (sustainability target)
Info::
At 10,000 monthly views: 149.5 kg CO2/year
With 10,000 page views per month, this page would generate approximately 149.5 kg of CO2 annually — equivalent to charging 18691 smartphones.

1.25g

Carbon Footprint per page view

✗ Above sustainability target (0.50g)

Cleaner than 32% of websites

Sustainable Web Design model v4 · Page size: 4.4 MB

Your site
1.25g
Top 10%
0.20g
Target
0.50g
Median website
0.60g

Energy Breakdown

Data center
0.23g
Network
0.22g
End-user device
0.80g
At 10,000 monthly views: Monthly: 12.5 kg · Annual: 149.5 kg · ≈ 18691 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 Snowplow Analytics✗CDN Not identified✗

Based on known provider commitments. Verify at thegreenwebfoundation.org

D
Carbon Budget
Action
68th percentile
FIX
68th percentile
Warning::
1.25g CO2 — above the median website (0.60g)
Heavier than an estimated 32% of websites. Reducing page weight, optimizing images, and removing unused JavaScript would lower the carbon footprint. See the Performance tab.
Info::
Estimated 68th percentile
Compared to: top 10% = 0.20g, target = 0.50g, median = 0.60g per page view.
Top 10%
Target
Median website

1.25g

68th percentile

Cleaner than 32% of websites

✗ Above the median website

vs Median 108% more
vs Target 149% more
C
Transfer Efficiency
Action
62% efficient
REVIEW
62% efficient
Warning::
Transfer efficiency: 62%
An estimated 1710 KB (38%) could be eliminated: 0 KB via better compression, 0 KB via modern image formats, 1710 KB of unused JavaScript. This wasted data produces 0.47g of unnecessary CO2 per page view.
62% efficient

Total waste: 1710 KB (38% of page weight)

Unused JS 1710 KB

0.47g unnecessary CO2 per visit

Actual transfer 4505 KB
Theoretical minimum 2794 KB
Potential savings 1710 KB (0.47g 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 117 KB (vs 4505 KB first visit). 124 of 128 resources are served from browser cache, saving 1.21g CO2 per repeat visit.
Info::
Repeat visit: 0.03g CO2 (first visit: 1.25g)
First visit
4505 KB
Repeat visit
117 KB

97% reduction on repeat visits

Saving 1.21g CO2 per returning visitor

124 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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