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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
72
GRADE
C
FIX
1
REVIEW
2
PASS
3
INFO
0
Device:
Mobile Desktop
Checks
6
3 PASS 2 REVIEW 1 FIX
D
Transfer Efficiency
Action
40% efficient
FIX
40% efficient
Critical::
Transfer efficiency: 40%
An estimated 1174 KB (60%) could be eliminated: 0 KB via better compression, 0 KB via modern image formats, 1174 KB of unused JavaScript. This wasted data produces 0.27g of unnecessary CO2 per page view.
40% efficient

Total waste: 1174 KB (60% of page weight)

Unused JS 1174 KB

0.27g unnecessary CO2 per visit

Actual transfer 1961 KB
Theoretical minimum 787 KB
Potential savings 1174 KB (0.27g CO2)

See Deep Analysis sections above for specific optimizations.

B
Carbon Budget
35th percentile
REVIEW
35th percentile
Info::
0.45g CO2 — below the sustainability target of 0.50g
Cleaner than an estimated 65% of websites analyzed. This page meets the Web Sustainability Guidelines target.
Info::
Estimated 35th percentile
Compared to: top 10% = 0.20g, target = 0.50g, median = 0.60g per page view.
Top 10%
Target
Median website

0.45g

35th percentile

Cleaner than 65% of websites

✓ Below the Web Sustainability Guidelines target

vs Median 24% cleaner ✓
vs Target 9% cleaner ✓
C
Green Hosting
Action
Whether the site is served from green-energy infrastructure
REVIEW

Green Hosting

No green hosting detected

A
CO2 Per Page Load
0.45g CO2 per view
PASS
0.45g CO2 per view
Info::
0.45g CO2 per page view
This page transfers 1.9 MB, producing an estimated 0.45g of CO2 per visit using the Sustainable Web Design model (v4). Breakdown: data center 0.01g, network 0.09g, end-user device 0.35g.
Got: 0.45g CO2 Expected: < 0.50g (sustainability target)
Info::
At 10,000 monthly views: 54.4 kg CO2/year
With 10,000 page views per month, this page would generate approximately 54.4 kg of CO2 annually — equivalent to charging 6799 smartphones.
Info::
Green hosting reduces data center emissions

0.45g

Carbon Footprint per page view

✓ Below sustainability target (0.50g)

Cleaner than 65% of websites

Sustainable Web Design model v4 · Page size: 1.9 MB

Your site
0.45g
Top 10%
0.20g
Target
0.50g
Median website
0.60g

Energy Breakdown

Data center
0.01g
Network
0.09g
End-user device
0.35g
At 10,000 monthly views: Monthly: 4.5 kg · Annual: 54.4 kg · ≈ 6799 smartphone charges
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
94% cached
PASS
94% cached
Info::
94% reduction on repeat visits
Returning visitors download only 121 KB (vs 1961 KB first visit). 92 of 96 resources are served from browser cache, saving 0.43g CO2 per repeat visit.
Info::
Repeat visit: 0.03g CO2 (first visit: 0.45g)
First visit
1961 KB
Repeat visit
121 KB

94% reduction on repeat visits

Saving 0.43g CO2 per returning visitor

92 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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