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https://ellenmacarthurfoundation.org

Sustainability

· 6 checks — CO2 emissions, green hosting, repeat-visit weight, carbon budget, and transfer efficiency rolled into one auditable list.
SCORE
81
GRADE
B
FIX
0
REVIEW
4
PASS
2
INFO
0
Device:
Mobile Desktop
Checks
6
2 PASS 4 REVIEW
B
CO2 Per Page Load
0.52g CO2 per view
REVIEW
0.52g CO2 per view
Info::
0.52g CO2 per page view
This page transfers 2.2 MB, producing an estimated 0.52g of CO2 per visit using the Sustainable Web Design model (v4). Breakdown: data center 0.01g, network 0.11g, end-user device 0.40g.
Got: 0.52g CO2 Expected: < 0.50g (sustainability target)
Info::
At 10,000 monthly views: 62.0 kg CO2/year
With 10,000 page views per month, this page would generate approximately 62.0 kg of CO2 annually — equivalent to charging 7755 smartphones.
Info::
Green hosting reduces data center emissions

0.52g

Carbon Footprint per page view

✗ Above sustainability target (0.50g)

Cleaner than 59% of websites

Sustainable Web Design model v4 · Page size: 2.2 MB

Your site
0.52g
Top 10%
0.20g
Target
0.50g
Median website
0.60g

Energy Breakdown

Data center
0.01g
Network
0.11g
End-user device
0.40g
At 10,000 monthly views: Monthly: 5.2 kg · Annual: 62.0 kg · ≈ 7755 smartphone charges
B
Carbon Budget
41th percentile
REVIEW
41th percentile
Info::
0.52g CO2 — below the median website (0.60g)
Better than an estimated 59% of websites, but above the sustainability target of 0.50g. Reducing page weight would help reach the target.
Info::
Estimated 41th percentile
Compared to: top 10% = 0.20g, target = 0.50g, median = 0.60g per page view.
Top 10%
Target
Median website

0.52g

41st percentile

Cleaner than 59% of websites

✗ Above the median website

vs Median 14% cleaner ✓
vs Target 3% more
B
Transfer Efficiency
82% efficient
REVIEW
82% efficient
Info::
Transfer efficiency: 82%
An estimated 407 KB (18%) could be eliminated: 0 KB via better compression, 0 KB via modern image formats, 407 KB of unused JavaScript. This wasted data produces 0.09g of unnecessary CO2 per page view.
82% efficient

Total waste: 407 KB (18% of page weight)

Unused JS 407 KB

0.09g unnecessary CO2 per visit

Actual transfer 2236 KB
Theoretical minimum 1829 KB
Potential savings 407 KB (0.09g 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
Green Hosting
Green (cdn)
PASS
Green (cdn)
Info::
Netlify CDN uses renewable energy
Since most traffic is served through the CDN, the majority of data transfer energy is renewable.
Info::
Netlify: Hosted on AWS/Google Cloud with renewable energy matching
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 Hosting✓ Green Hosted
Hosting Not identified✗CDN Netlify✓

Netlify: Hosted on AWS/Google Cloud with renewable energy matching

Based on known provider commitments. Verify at thegreenwebfoundation.org

A+
Repeat Visit Weight
83% cached
PASS
83% cached
Info::
83% reduction on repeat visits
Returning visitors download only 386 KB (vs 2236 KB first visit). 101 of 103 resources are served from browser cache, saving 0.43g CO2 per repeat visit.
Info::
Repeat visit: 0.09g CO2 (first visit: 0.52g)
First visit
2236 KB
Repeat visit
386 KB

83% reduction on repeat visits

Saving 0.43g CO2 per returning visitor

101 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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