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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
0.90g CO2 per view
FIX
0.90g CO2 per view
Info::
0.90g CO2 per page view
This page transfers 3.2 MB, producing an estimated 0.90g of CO2 per visit using the Sustainable Web Design model (v4). Breakdown: data center 0.17g, network 0.16g, end-user device 0.58g.
Got: 0.90g CO2 Expected: < 0.50g (sustainability target)
Info::
At 10,000 monthly views: 107.9 kg CO2/year
With 10,000 page views per month, this page would generate approximately 107.9 kg of CO2 annually — equivalent to charging 13482 smartphones.

0.90g

Carbon Footprint per page view

✗ Above sustainability target (0.50g)

Cleaner than 42% of websites

Sustainable Web Design model v4 · Page size: 3.2 MB

Your site
0.90g
Top 10%
0.20g
Target
0.50g
Median website
0.60g

Energy Breakdown

Data center
0.17g
Network
0.16g
End-user device
0.58g
At 10,000 monthly views: Monthly: 9.0 kg · Annual: 107.9 kg · ≈ 13482 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::
Akamai: Committed to 50% renewable by 2030
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 Akamai✗

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

Akamai: Committed to 50% renewable by 2030

Based on known provider commitments. Verify at thegreenwebfoundation.org

D
Carbon Budget
Action
58th percentile
FIX
58th percentile
Warning::
0.90g CO2 — above the median website (0.60g)
Heavier than an estimated 42% of websites. Reducing page weight, optimizing images, and removing unused JavaScript would lower the carbon footprint. See the Performance tab.
Info::
Estimated 58th percentile
Compared to: top 10% = 0.20g, target = 0.50g, median = 0.60g per page view.
Top 10%
Target
Median website

0.90g

58th percentile

Cleaner than 42% of websites

✗ Above the median website

vs Median 50% more
vs Target 80% more
C
Transfer Efficiency
Action
64% efficient
REVIEW
64% efficient
Warning::
Transfer efficiency: 64%
An estimated 1183 KB (36%) could be eliminated: 0 KB via better compression, 0 KB via modern image formats, 1183 KB of unused JavaScript. This wasted data produces 0.33g of unnecessary CO2 per page view.
64% efficient

Total waste: 1183 KB (36% of page weight)

Unused JS 1183 KB

0.33g unnecessary CO2 per visit

Actual transfer 3250 KB
Theoretical minimum 2066 KB
Potential savings 1183 KB (0.33g 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
100% cached
PASS
100% cached
Info::
100% reduction on repeat visits
Returning visitors download only 14 KB (vs 3250 KB first visit). 168 of 170 resources are served from browser cache, saving 0.89g CO2 per repeat visit.
Info::
Repeat visit: 0.00g CO2 (first visit: 0.90g)
First visit
3250 KB
Repeat visit
14 KB

100% reduction on repeat visits

Saving 0.89g CO2 per returning visitor

168 resources served from cache · 2 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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