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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
69
GRADE
D
FIX
2
REVIEW
3
PASS
1
INFO
0
Device:
Mobile Desktop
Checks
6
1 PASS 3 REVIEW 2 FIX
D
CO2 Per Page Load
Action
1.13g CO2 per view
FIX
1.13g CO2 per view
Warning::
1.13g CO2 per page view
This page transfers 4.8 MB, producing an estimated 1.13g of CO2 per visit using the Sustainable Web Design model (v4). Breakdown: data center 0.03g, network 0.23g, end-user device 0.87g.
Got: 1.13g CO2 Expected: < 0.50g (sustainability target)
Info::
At 10,000 monthly views: 135.8 kg CO2/year
With 10,000 page views per month, this page would generate approximately 135.8 kg of CO2 annually — equivalent to charging 16976 smartphones.
Info::
Green hosting reduces data center emissions

1.13g

Carbon Footprint per page view

✗ Above sustainability target (0.50g)

Cleaner than 35% of websites

Sustainable Web Design model v4 · Page size: 4.8 MB

Your site
1.13g
Top 10%
0.20g
Target
0.50g
Median website
0.60g

Energy Breakdown

Data center
0.03g
Network
0.23g
End-user device
0.87g
At 10,000 monthly views: Monthly: 11.3 kg · Annual: 135.8 kg · ≈ 16976 smartphone charges
D
Carbon Budget
Action
65th percentile
FIX
65th percentile
Warning::
1.13g CO2 — above the median website (0.60g)
Heavier than an estimated 35% of websites. Reducing page weight, optimizing images, and removing unused JavaScript would lower the carbon footprint. See the Performance tab.
Info::
Estimated 65th percentile
Compared to: top 10% = 0.20g, target = 0.50g, median = 0.60g per page view.
Top 10%
Target
Median website

1.13g

65th percentile

Cleaner than 35% of websites

✗ Above the median website

vs Median 89% more
vs Target 126% more
B
Repeat Visit Weight
79% cached
REVIEW
79% cached
Info::
79% reduction on repeat visits
Returning visitors download only 1030 KB (vs 4896 KB first visit). 254 of 257 resources are served from browser cache, saving 0.89g CO2 per repeat visit.
Info::
Repeat visit: 0.24g CO2 (first visit: 1.13g)
First visit
4896 KB
Repeat visit
1030 KB

79% reduction on repeat visits

Saving 0.89g CO2 per returning visitor

254 resources served from cache · 3 resources re-downloaded

B
Transfer Efficiency
79% efficient
REVIEW
79% efficient
Info::
Transfer efficiency: 79%
An estimated 1023 KB (21%) could be eliminated: 0 KB via better compression, 0 KB via modern image formats, 1023 KB of unused JavaScript. This wasted data produces 0.24g of unnecessary CO2 per page view.
79% efficient

Total waste: 1023 KB (21% of page weight)

Unused JS 1023 KB

0.24g unnecessary CO2 per visit

Actual transfer 4896 KB
Theoretical minimum 3872 KB
Potential savings 1023 KB (0.24g 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
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

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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