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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
89
GRADE
B
FIX
0
REVIEW
2
PASS
4
INFO
0
Device:
Mobile Desktop
Checks
6
4 PASS 2 REVIEW
B
Transfer Efficiency
78% efficient
REVIEW
78% efficient
Info::
Transfer efficiency: 78%
An estimated 204 KB (22%) could be eliminated: 0 KB via better compression, 0 KB via modern image formats, 204 KB of unused JavaScript. This wasted data produces 0.05g of unnecessary CO2 per page view.
78% efficient

Total waste: 204 KB (22% of page weight)

Unused JS 204 KB

0.05g unnecessary CO2 per visit

Actual transfer 949 KB
Theoretical minimum 744 KB
Potential savings 204 KB (0.05g 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
CO2 Per Page Load
0.22g CO2 per view
PASS
0.22g CO2 per view
Info::
0.22g CO2 per page view
This page transfers 0.9 MB, producing an estimated 0.22g of CO2 per visit using the Sustainable Web Design model (v4). Breakdown: data center 0.01g, network 0.05g, end-user device 0.17g.
Got: 0.22g CO2 Expected: < 0.50g (sustainability target)
Info::
At 10,000 monthly views: 26.3 kg CO2/year
With 10,000 page views per month, this page would generate approximately 26.3 kg of CO2 annually — equivalent to charging 3290 smartphones.
Info::
Green hosting reduces data center emissions

0.22g

Carbon Footprint per page view

✓ Below sustainability target (0.50g)

Cleaner than 89% of websites

Sustainable Web Design model v4 · Page size: 0.9 MB

Your site
0.22g
Top 10%
0.20g
Target
0.50g
Median website
0.60g

Energy Breakdown

Data center
0.01g
Network
0.05g
End-user device
0.17g
At 10,000 monthly views: Monthly: 2.2 kg · Annual: 26.3 kg · ≈ 3290 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
98% cached
PASS
98% cached
Info::
98% reduction on repeat visits
Returning visitors download only 15 KB (vs 949 KB first visit). 22 of 24 resources are served from browser cache, saving 0.22g CO2 per repeat visit.
Info::
Repeat visit: 0.00g CO2 (first visit: 0.22g)
First visit
949 KB
Repeat visit
15 KB

98% reduction on repeat visits

Saving 0.22g CO2 per returning visitor

22 resources served from cache · 2 resources re-downloaded

A
Carbon Budget
11th percentile
PASS
11th percentile
Info::
0.22g CO2 — below the sustainability target of 0.50g
Cleaner than an estimated 89% of websites analyzed. This page meets the Web Sustainability Guidelines target.
Info::
Estimated 11th percentile
Compared to: top 10% = 0.20g, target = 0.50g, median = 0.60g per page view.
Top 10%
Target
Median website

0.22g

11th percentile

Cleaner than 89% of websites

✓ Below the Web Sustainability Guidelines target

vs Median 63% cleaner ✓
vs Target 56% cleaner ✓
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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