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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
80
GRADE
B
FIX
0
REVIEW
3
PASS
3
INFO
0
Device:
Mobile Desktop
Checks
6
3 PASS 3 REVIEW
B
Carbon Budget
38th percentile
REVIEW
38th percentile
Info::
0.48g CO2 — below the sustainability target of 0.50g
Cleaner than an estimated 62% of websites analyzed. This page meets the Web Sustainability Guidelines target.
Info::
Estimated 38th percentile
Compared to: top 10% = 0.20g, target = 0.50g, median = 0.60g per page view.
Top 10%
Target
Median website

0.48g

38th percentile

Cleaner than 62% of websites

✓ Below the Web Sustainability Guidelines target

vs Median 20% cleaner ✓
vs Target 4% cleaner ✓
C
Transfer Efficiency
Action
70% efficient
REVIEW
70% efficient
Warning::
Transfer efficiency: 70%
An estimated 631 KB (30%) could be eliminated: 0 KB via better compression, 0 KB via modern image formats, 631 KB of unused JavaScript. This wasted data produces 0.15g of unnecessary CO2 per page view.
70% efficient

Total waste: 631 KB (30% of page weight)

Unused JS 631 KB

0.15g unnecessary CO2 per visit

Actual transfer 2080 KB
Theoretical minimum 1448 KB
Potential savings 631 KB (0.15g 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
0.48g CO2 per view
PASS
0.48g CO2 per view
Info::
0.48g CO2 per page view
This page transfers 2.0 MB, producing an estimated 0.48g of CO2 per visit using the Sustainable Web Design model (v4). Breakdown: data center 0.01g, network 0.10g, end-user device 0.37g.
Got: 0.48g CO2 Expected: < 0.50g (sustainability target)
Info::
At 10,000 monthly views: 57.7 kg CO2/year
With 10,000 page views per month, this page would generate approximately 57.7 kg of CO2 annually — equivalent to charging 7212 smartphones.
Info::
Green hosting reduces data center emissions

0.48g

Carbon Footprint per page view

✓ Below sustainability target (0.50g)

Cleaner than 62% of websites

Sustainable Web Design model v4 · Page size: 2.0 MB

Your site
0.48g
Top 10%
0.20g
Target
0.50g
Median website
0.60g

Energy Breakdown

Data center
0.01g
Network
0.10g
End-user device
0.37g
At 10,000 monthly views: Monthly: 4.8 kg · Annual: 57.7 kg · ≈ 7212 smartphone charges
A
Green Hosting
Green (cdn)
PASS
Green (cdn)
Info::
Vercel CDN uses renewable energy
Since most traffic is served through the CDN, the majority of data transfer energy is renewable.
Info::
Vercel: Hosted on AWS/Google Cloud with renewable energy commitments
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 Next.js✗CDN Vercel✓

Vercel: Hosted on AWS/Google Cloud with renewable energy commitments

Based on known provider commitments. Verify at thegreenwebfoundation.org

A+
Repeat Visit Weight
99% cached
PASS
99% cached
Info::
99% reduction on repeat visits
Returning visitors download only 24 KB (vs 2080 KB first visit). 154 of 156 resources are served from browser cache, saving 0.48g CO2 per repeat visit.
Info::
Repeat visit: 0.01g CO2 (first visit: 0.48g)
First visit
2080 KB
Repeat visit
24 KB

99% reduction on repeat visits

Saving 0.48g CO2 per returning visitor

154 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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