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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
65
GRADE
D
FIX
2
REVIEW
1
PASS
3
INFO
0
Device:
Mobile Desktop
Checks
6
3 PASS 1 REVIEW 2 FIX
F
CO2 Per Page Load
Action
4.18g CO2 per view
FIX
4.18g CO2 per view
Critical::
4.18g CO2 per page view
This page transfers 17.7 MB, producing an estimated 4.18g of CO2 per visit using the Sustainable Web Design model (v4). Breakdown: data center 0.10g, network 0.86g, end-user device 3.21g.
Got: 4.18g CO2 Expected: < 0.50g (sustainability target)
Info::
At 10,000 monthly views: 501.6 kg CO2/year
With 10,000 page views per month, this page would generate approximately 501.6 kg of CO2 annually — equivalent to charging 62701 smartphones.
Info::
Green hosting reduces data center emissions

4.18g

Carbon Footprint per page view

✗ Above sustainability target (0.50g)

Cleaner than 5% of websites

Sustainable Web Design model v4 · Page size: 17.7 MB

Your site
4.18g
Top 10%
0.20g
Target
0.50g
Median website
0.60g

Energy Breakdown

Data center
0.10g
Network
0.86g
End-user device
3.21g
At 10,000 monthly views: Monthly: 41.8 kg · Annual: 501.6 kg · ≈ 62701 smartphone charges
F
Carbon Budget
Action
95th percentile
FIX
95th percentile
Warning::
4.18g CO2 — above the median website (0.60g)
Heavier than an estimated 5% of websites. Reducing page weight, optimizing images, and removing unused JavaScript would lower the carbon footprint. See the Performance tab.
Info::
Estimated 95th percentile
Compared to: top 10% = 0.20g, target = 0.50g, median = 0.60g per page view.
Top 10%
Target
Median website

4.18g

95th percentile

Cleaner than 5% of websites

✗ Above the median website

vs Median 597% more
vs Target 736% 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 (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 97 KB (vs 18084 KB first visit). 145 of 149 resources are served from browser cache, saving 4.16g CO2 per repeat visit.
Info::
Repeat visit: 0.02g CO2 (first visit: 4.18g)
First visit
18084 KB
Repeat visit
97 KB

99% reduction on repeat visits

Saving 4.16g CO2 per returning visitor

145 resources served from cache · 4 resources re-downloaded

A+
Transfer Efficiency
95% efficient
PASS
95% efficient
Info::
Transfer efficiency: 95%
Only 918 KB of potential savings identified. Your page is well-optimized for size.
95% efficient

Total waste: 918 KB (5% of page weight)

Unused JS 918 KB

0.21g unnecessary CO2 per visit

Actual transfer 18084 KB
Theoretical minimum 17166 KB
Potential savings 918 KB (0.21g CO2)

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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