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https://a16z.com

Sustainability

· 6 checks — CO2 emissions, green hosting, repeat-visit weight, carbon budget, and transfer efficiency rolled into one auditable list.
SCORE
66
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
2.94g CO2 per view
FIX
2.94g CO2 per view
Critical::
2.94g CO2 per page view
This page transfers 12.4 MB, producing an estimated 2.94g of CO2 per visit using the Sustainable Web Design model (v4). Breakdown: data center 0.07g, network 0.61g, end-user device 2.26g.
Got: 2.94g CO2 Expected: < 0.50g (sustainability target)
Info::
At 10,000 monthly views: 352.8 kg CO2/year
With 10,000 page views per month, this page would generate approximately 352.8 kg of CO2 annually — equivalent to charging 44104 smartphones.
Info::
Green hosting reduces data center emissions

2.94g

Carbon Footprint per page view

✗ Above sustainability target (0.50g)

Cleaner than 5% of websites

Sustainable Web Design model v4 · Page size: 12.4 MB

Your site
2.94g
Top 10%
0.20g
Target
0.50g
Median website
0.60g

Energy Breakdown

Data center
0.07g
Network
0.61g
End-user device
2.26g
At 10,000 monthly views: Monthly: 29.4 kg · Annual: 352.8 kg · ≈ 44104 smartphone charges
F
Carbon Budget
Action
95th percentile
FIX
95th percentile
Warning::
2.94g 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

2.94g

95th percentile

Cleaner than 5% of websites

✗ Above the median website

vs Median 390% more
vs Target 488% 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::
Netlify CDN uses renewable energy
Since most traffic is served through the CDN, the majority of data transfer energy is renewable.
Info::
Netlify: Hosted on AWS/Google Cloud with renewable energy matching
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 Not identified✗CDN Netlify✓

Netlify: Hosted on AWS/Google Cloud with renewable energy matching

Based on known provider commitments. Verify at thegreenwebfoundation.org

A+
Repeat Visit Weight
100% cached
PASS
100% cached
Info::
100% reduction on repeat visits
Returning visitors download only 20 KB (vs 12720 KB first visit). 20 of 21 resources are served from browser cache, saving 2.94g CO2 per repeat visit.
Info::
Repeat visit: 0.00g CO2 (first visit: 2.94g)
First visit
12720 KB
Repeat visit
20 KB

100% reduction on repeat visits

Saving 2.94g CO2 per returning visitor

20 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 12720 KB
Theoretical minimum 12720 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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