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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
76
GRADE
C
FIX
1
REVIEW
3
PASS
2
INFO
0
Device:
Mobile Desktop
Checks
6
2 PASS 3 REVIEW 1 FIX
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 Acquia Cloud Platform✗CDN Sucuri✗

Based on known provider commitments. Verify at thegreenwebfoundation.org

B
CO2 Per Page Load
0.60g CO2 per view
REVIEW
0.60g CO2 per view
Info::
0.60g CO2 per page view
This page transfers 2.1 MB, producing an estimated 0.60g of CO2 per visit using the Sustainable Web Design model (v4). Breakdown: data center 0.11g, network 0.10g, end-user device 0.39g.
Got: 0.60g CO2 Expected: < 0.50g (sustainability target)
Info::
At 10,000 monthly views: 72.0 kg CO2/year
With 10,000 page views per month, this page would generate approximately 72.0 kg of CO2 annually — equivalent to charging 9000 smartphones.

0.60g

Carbon Footprint per page view

✗ Above sustainability target (0.50g)

Cleaner than 50% of websites

Sustainable Web Design model v4 · Page size: 2.1 MB

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

Energy Breakdown

Data center
0.11g
Network
0.10g
End-user device
0.39g
At 10,000 monthly views: Monthly: 6.0 kg · Annual: 72.0 kg · ≈ 9000 smartphone charges
B
Carbon Budget
50th percentile
REVIEW
50th percentile
Warning::
0.60g CO2 — above the median website (0.60g)
Heavier than an estimated 50% of websites. Reducing page weight, optimizing images, and removing unused JavaScript would lower the carbon footprint. See the Performance tab.
Info::
Estimated 50th percentile
Compared to: top 10% = 0.20g, target = 0.50g, median = 0.60g per page view.
Top 10%
Target
Median website

0.60g

50th percentile

Cleaner than 50% of websites

✗ Above the median website

vs Median 0% more
vs Target 20% more
C
Green Hosting
Action
Whether the site is served from green-energy infrastructure
REVIEW

Green Hosting

No green hosting detected

A+
Repeat Visit Weight
99% cached
PASS
99% cached
Info::
99% reduction on repeat visits
Returning visitors download only 30 KB (vs 2169 KB first visit). 96 of 99 resources are served from browser cache, saving 0.59g CO2 per repeat visit.
Info::
Repeat visit: 0.01g CO2 (first visit: 0.60g)
First visit
2169 KB
Repeat visit
30 KB

99% reduction on repeat visits

Saving 0.59g CO2 per returning visitor

96 resources served from cache · 3 resources re-downloaded

A+
Transfer Efficiency
90% efficient
PASS
90% efficient
Info::
Transfer efficiency: 90%
Only 214 KB of potential savings identified. Your page is well-optimized for size.
90% efficient

Total waste: 214 KB (10% of page weight)

Unused JS 214 KB

0.06g unnecessary CO2 per visit

Actual transfer 2169 KB
Theoretical minimum 1955 KB
Potential savings 214 KB (0.06g CO2)

See Deep Analysis sections above for specific optimizations.

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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