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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
91
GRADE
A
FIX
0
REVIEW
2
PASS
4
INFO
0
Device:
Mobile Desktop
Checks
6
4 PASS 2 REVIEW
B
Carbon Budget
39th percentile
REVIEW
39th percentile
Info::
0.50g CO2 — below the sustainability target of 0.50g
Cleaner than an estimated 61% of websites analyzed. This page meets the Web Sustainability Guidelines target.
Info::
Estimated 39th percentile
Compared to: top 10% = 0.20g, target = 0.50g, median = 0.60g per page view.
Top 10%
Target
Median website

0.50g

39th percentile

Cleaner than 61% of websites

✓ Below the Web Sustainability Guidelines target

vs Median 17% cleaner ✓
vs Target 1% cleaner ✓
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
0.50g CO2 per view
PASS
0.50g CO2 per view
Info::
0.50g CO2 per page view
This page transfers 2.1 MB, producing an estimated 0.50g of CO2 per visit using the Sustainable Web Design model (v4). Breakdown: data center 0.01g, network 0.10g, end-user device 0.38g.
Got: 0.50g CO2 Expected: < 0.50g (sustainability target)
Info::
At 10,000 monthly views: 59.6 kg CO2/year
With 10,000 page views per month, this page would generate approximately 59.6 kg of CO2 annually — equivalent to charging 7450 smartphones.
Info::
Green hosting reduces data center emissions

0.50g

Carbon Footprint per page view

✓ Below sustainability target (0.50g)

Cleaner than 61% of websites

Sustainable Web Design model v4 · Page size: 2.1 MB

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

Energy Breakdown

Data center
0.01g
Network
0.10g
End-user device
0.38g
At 10,000 monthly views: Monthly: 5.0 kg · Annual: 59.6 kg · ≈ 7450 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
98% cached
PASS
98% cached
Info::
98% reduction on repeat visits
Returning visitors download only 51 KB (vs 2148 KB first visit). 143 of 144 resources are served from browser cache, saving 0.48g CO2 per repeat visit.
Info::
Repeat visit: 0.01g CO2 (first visit: 0.50g)
First visit
2148 KB
Repeat visit
51 KB

98% reduction on repeat visits

Saving 0.48g CO2 per returning visitor

143 resources served from cache · 1 resources re-downloaded

A+
Transfer Efficiency
93% efficient
PASS
93% efficient
Info::
Transfer efficiency: 93%
Only 145 KB of potential savings identified. Your page is well-optimized for size.
93% efficient

Total waste: 145 KB (7% of page weight)

Unused JS 145 KB

0.03g unnecessary CO2 per visit

Actual transfer 2148 KB
Theoretical minimum 2003 KB
Potential savings 145 KB (0.03g 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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