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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
2
REVIEW
1
PASS
3
INFO
0
Device:
Mobile Desktop
Checks
6
3 PASS 1 REVIEW 2 FIX
D
CO2 Per Page Load
Action
0.95g CO2 per view
FIX
0.95g CO2 per view
Info::
0.95g CO2 per page view
This page transfers 4.0 MB, producing an estimated 0.95g of CO2 per visit using the Sustainable Web Design model (v4). Breakdown: data center 0.02g, network 0.20g, end-user device 0.73g.
Got: 0.95g CO2 Expected: < 0.50g (sustainability target)
Info::
At 10,000 monthly views: 114.4 kg CO2/year
With 10,000 page views per month, this page would generate approximately 114.4 kg of CO2 annually — equivalent to charging 14297 smartphones.
Info::
Green hosting reduces data center emissions

0.95g

Carbon Footprint per page view

✗ Above sustainability target (0.50g)

Cleaner than 40% of websites

Sustainable Web Design model v4 · Page size: 4.0 MB

Your site
0.95g
Top 10%
0.20g
Target
0.50g
Median website
0.60g

Energy Breakdown

Data center
0.02g
Network
0.20g
End-user device
0.73g
At 10,000 monthly views: Monthly: 9.5 kg · Annual: 114.4 kg · ≈ 14297 smartphone charges
D
Carbon Budget
Action
60th percentile
FIX
60th percentile
Warning::
0.95g CO2 — above the median website (0.60g)
Heavier than an estimated 40% of websites. Reducing page weight, optimizing images, and removing unused JavaScript would lower the carbon footprint. See the Performance tab.
Info::
Estimated 60th percentile
Compared to: top 10% = 0.20g, target = 0.50g, median = 0.60g per page view.
Top 10%
Target
Median website

0.95g

60th percentile

Cleaner than 40% of websites

✗ Above the median website

vs Median 59% more
vs Target 91% more
C
Green Hosting
Action
Whether the site is served from green-energy infrastructure
REVIEW

Green Hosting

No green hosting detected

A+
Green Hosting
Green (both)
PASS
Green (both)
Info::
Both hosting and CDN use renewable energy
Got: Hosting: Vercel, CDN: Vercel
Info::
Vercel: Hosted on AWS/Google Cloud with renewable energy commitments
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 Vercel✓CDN Vercel✓

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

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 23 KB (vs 4123 KB first visit). 76 of 77 resources are served from browser cache, saving 0.95g CO2 per repeat visit.
Info::
Repeat visit: 0.01g CO2 (first visit: 0.95g)
First visit
4123 KB
Repeat visit
23 KB

99% reduction on repeat visits

Saving 0.95g CO2 per returning visitor

76 resources served from cache · 1 resources re-downloaded

A+
Transfer Efficiency
100% efficient
PASS
100% efficient
Info::
Transfer efficiency: 100%
Only 0 KB of potential savings identified. Your page is well-optimized for size.
100% efficient
Actual transfer 4123 KB
Theoretical minimum 4123 KB

See Deep Analysis sections above for specific optimizations.

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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