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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
93
GRADE
A
FIX
0
REVIEW
2
PASS
4
INFO
0
Device:
Mobile Desktop
Checks
6
4 PASS 2 REVIEW
B
Transfer Efficiency
85% efficient
REVIEW
85% efficient
Info::
Transfer efficiency: 85%
An estimated 49 KB (15%) could be eliminated: 0 KB via better compression, 0 KB via modern image formats, 49 KB of unused JavaScript. This wasted data produces 0.01g of unnecessary CO2 per page view.
85% efficient

Total waste: 49 KB (15% of page weight)

Unused JS 49 KB

0.01g unnecessary CO2 per visit

Actual transfer 323 KB
Theoretical minimum 274 KB
Potential savings 49 KB (0.01g 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
0.07g CO2 per view
PASS
0.07g CO2 per view
Info::
0.07g CO2 per page view
This page transfers 0.3 MB, producing an estimated 0.07g of CO2 per visit using the Sustainable Web Design model (v4). Breakdown: data center 0.00g, network 0.02g, end-user device 0.06g.
Got: 0.07g CO2 Expected: < 0.50g (sustainability target)
Info::
At 10,000 monthly views: 9.0 kg CO2/year
With 10,000 page views per month, this page would generate approximately 9.0 kg of CO2 annually — equivalent to charging 1123 smartphones.
Info::
Green hosting reduces data center emissions

0.07g

Carbon Footprint per page view

✓ Below sustainability target (0.50g)

Cleaner than 90% of websites

Sustainable Web Design model v4 · Page size: 0.3 MB

Your site
0.07g
Top 10%
0.20g
Target
0.50g
Median website
0.60g

Energy Breakdown

Data center
0.00g
Network
0.02g
End-user device
0.06g
At 10,000 monthly views: Monthly: 0.7 kg · Annual: 9.0 kg · ≈ 1123 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 5 KB (vs 323 KB first visit). 36 of 37 resources are served from browser cache, saving 0.07g CO2 per repeat visit.
Info::
Repeat visit: 0.00g CO2 (first visit: 0.07g)
First visit
323 KB
Repeat visit
5 KB

98% reduction on repeat visits

Saving 0.07g CO2 per returning visitor

36 resources served from cache · 1 resources re-downloaded

A+
Carbon Budget
10th percentile
PASS
10th percentile
Info::
0.07g CO2 — below the sustainability target of 0.50g
Cleaner than an estimated 90% of websites analyzed. This page meets the Web Sustainability Guidelines target.
Info::
Estimated 10th percentile
Compared to: top 10% = 0.20g, target = 0.50g, median = 0.60g per page view.
Top 10%
Target
Median website

0.07g

10th percentile

Cleaner than 90% of websites

✓ Below the Web Sustainability Guidelines target

vs Median 88% cleaner ✓
vs Target 85% 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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