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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
60
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
1.07g CO2 per view
FIX
1.07g CO2 per view
Warning::
1.07g CO2 per page view
This page transfers 3.8 MB, producing an estimated 1.07g of CO2 per visit using the Sustainable Web Design model (v4). Breakdown: data center 0.20g, network 0.19g, end-user device 0.69g.
Got: 1.07g CO2 Expected: < 0.50g (sustainability target)
Info::
At 10,000 monthly views: 128.4 kg CO2/year
With 10,000 page views per month, this page would generate approximately 128.4 kg of CO2 annually — equivalent to charging 16056 smartphones.

1.07g

Carbon Footprint per page view

✗ Above sustainability target (0.50g)

Cleaner than 37% of websites

Sustainable Web Design model v4 · Page size: 3.8 MB

Your site
1.07g
Top 10%
0.20g
Target
0.50g
Median website
0.60g

Energy Breakdown

Data center
0.20g
Network
0.19g
End-user device
0.69g
At 10,000 monthly views: Monthly: 10.7 kg · Annual: 128.4 kg · ≈ 16056 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::
AWS: Renewable energy varies by region; committed to 100% by 2025
Info::
AWS CloudFront: Renewable varies by edge location
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 AWS✗CDN AWS CloudFront✗

AWS: Renewable energy varies by region; committed to 100% by 2025

AWS CloudFront: Renewable varies by edge location

Based on known provider commitments. Verify at thegreenwebfoundation.org

D
Carbon Budget
Action
63th percentile
FIX
63th percentile
Warning::
1.07g CO2 — above the median website (0.60g)
Heavier than an estimated 37% of websites. Reducing page weight, optimizing images, and removing unused JavaScript would lower the carbon footprint. See the Performance tab.
Info::
Estimated 63th percentile
Compared to: top 10% = 0.20g, target = 0.50g, median = 0.60g per page view.
Top 10%
Target
Median website

1.07g

63rd percentile

Cleaner than 37% of websites

✗ Above the median website

vs Median 78% more
vs Target 114% more
C
Transfer Efficiency
Action
71% efficient
REVIEW
71% efficient
Warning::
Transfer efficiency: 71%
An estimated 1113 KB (29%) could be eliminated: 0 KB via better compression, 0 KB via modern image formats, 1113 KB of unused JavaScript. This wasted data produces 0.31g of unnecessary CO2 per page view.
71% efficient

Total waste: 1113 KB (29% of page weight)

Unused JS 1113 KB

0.31g unnecessary CO2 per visit

Actual transfer 3870 KB
Theoretical minimum 2756 KB
Potential savings 1113 KB (0.31g 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 108 KB (vs 3870 KB first visit). 219 of 227 resources are served from browser cache, saving 1.04g CO2 per repeat visit.
Info::
Repeat visit: 0.03g CO2 (first visit: 1.07g)
First visit
3870 KB
Repeat visit
108 KB

97% reduction on repeat visits

Saving 1.04g CO2 per returning visitor

219 resources served from cache · 8 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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