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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
73
GRADE
C
FIX
1
REVIEW
3
PASS
2
INFO
0
Device:
Mobile Desktop
Checks
6
2 PASS 3 REVIEW 1 FIX
D
Transfer Efficiency
Action
45% efficient
FIX
45% efficient
Critical::
Transfer efficiency: 45%
An estimated 1448 KB (55%) could be eliminated: 0 KB via better compression, 0 KB via modern image formats, 1448 KB of unused JavaScript. This wasted data produces 0.33g of unnecessary CO2 per page view.
45% efficient

Total waste: 1448 KB (55% of page weight)

Unused JS 1448 KB

0.33g unnecessary CO2 per visit

Actual transfer 2653 KB
Theoretical minimum 1205 KB
Potential savings 1448 KB (0.33g CO2)

See Deep Analysis sections above for specific optimizations.

B
CO2 Per Page Load
0.61g CO2 per view
REVIEW
0.61g CO2 per view
Info::
0.61g CO2 per page view
This page transfers 2.6 MB, producing an estimated 0.61g of CO2 per visit using the Sustainable Web Design model (v4). Breakdown: data center 0.02g, network 0.13g, end-user device 0.47g.
Got: 0.61g CO2 Expected: < 0.50g (sustainability target)
Info::
At 10,000 monthly views: 73.6 kg CO2/year
With 10,000 page views per month, this page would generate approximately 73.6 kg of CO2 annually — equivalent to charging 9201 smartphones.
Info::
Green hosting reduces data center emissions

0.61g

Carbon Footprint per page view

✗ Above sustainability target (0.50g)

Cleaner than 50% of websites

Sustainable Web Design model v4 · Page size: 2.6 MB

Your site
0.61g
Top 10%
0.20g
Target
0.50g
Median website
0.60g

Energy Breakdown

Data center
0.02g
Network
0.13g
End-user device
0.47g
At 10,000 monthly views: Monthly: 6.1 kg · Annual: 73.6 kg · ≈ 9201 smartphone charges
B
Carbon Budget
50th percentile
REVIEW
50th percentile
Warning::
0.61g CO2 — above the median website (0.60g)
Heavier than an estimated 50% of websites. Reducing page weight, optimizing images, and removing unused JavaScript would lower the carbon footprint. See the Performance tab.
Info::
Estimated 50th percentile
Compared to: top 10% = 0.20g, target = 0.50g, median = 0.60g per page view.
Top 10%
Target
Median website

0.61g

50th percentile

Cleaner than 50% of websites

✗ Above the median website

vs Median 2% more
vs Target 23% 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
95% cached
PASS
95% cached
Info::
95% reduction on repeat visits
Returning visitors download only 121 KB (vs 2653 KB first visit). 111 of 115 resources are served from browser cache, saving 0.59g CO2 per repeat visit.
Info::
Repeat visit: 0.03g CO2 (first visit: 0.61g)
First visit
2653 KB
Repeat visit
121 KB

95% reduction on repeat visits

Saving 0.59g CO2 per returning visitor

111 resources served from cache · 4 resources re-downloaded

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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