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https://libsyn.com

Sustainability

· 6 checks — CO2 emissions, green hosting, repeat-visit weight, carbon budget, and transfer efficiency rolled into one auditable list.
SCORE
76
GRADE
C
FIX
2
REVIEW
1
PASS
3
INFO
0
Checks
6
3 PASS 1 REVIEW 2 FIX
D
CO2 Per Page Load
Action
0.97g CO2 per view
FIX
0.97g CO2 per view
Info::
0.97g CO2 per page view
This page transfers 4.1 MB, producing an estimated 0.97g of CO2 per visit using the Sustainable Web Design model (v4). Breakdown: data center 0.02g, network 0.20g, end-user device 0.75g.
Got: 0.97g CO2 Expected: < 0.50g (sustainability target)
Info::
At 10,000 monthly views: 116.7 kg CO2/year
With 10,000 page views per month, this page would generate approximately 116.7 kg of CO2 annually — equivalent to charging 14589 smartphones.
Info::
Green hosting reduces data center emissions

0.97g

Carbon Footprint per page view

Above sustainability target (0.50g)

Cleaner than 40% of websites

Sustainable Web Design model v4 · Page size: 4.1 MB

Your site
0.97g
Top 10%
0.20g
Target
0.50g
Median website
0.60g

Energy Breakdown

Data center
0.02g
Network
0.20g
End-user device
0.75g
At 10,000 monthly views: Monthly: 9.7 kg · Annual: 116.7 kg · ≈ 14589 smartphone charges
D
Carbon Budget
Action
60th percentile
FIX
60th percentile
Warning::
0.97g CO2 — above the median website (0.60g)
Heavier than an estimated 40% of websites. Reducing page weight, optimizing images, and removing unused JavaScript would lower the carbon footprint. See the Performance tab.
Info::
Estimated 60th percentile
Compared to: top 10% = 0.20g, target = 0.50g, median = 0.60g per page view.
Top 10%
Target
Median website

0.97g

60th percentile

Cleaner than 40% of websites

Above the median website

vs Median 62% more
vs Target 95% more
B
Transfer Efficiency
85% efficient
REVIEW
85% efficient
Info::
Transfer efficiency: 85%
An estimated 616 KB (15%) could be eliminated: 0 KB via better compression, 0 KB via modern image formats, 616 KB of unused JavaScript. This wasted data produces 0.14g of unnecessary CO2 per page view.
85% efficient

Total waste: 616 KB (15% of page weight)

Unused JS 616 KB

0.14g unnecessary CO2 per visit

Actual transfer 4208 KB
Theoretical minimum 3592 KB
Potential savings 616 KB (0.14g CO2)

See Deep Analysis sections above for specific optimizations.

A+
Green Hosting
Green (both)
PASS
Green (both)
Info::
Both hosting and CDN use renewable energy
Got: Hosting: Cloudflare, CDN: Cloudflare
Info::
Cloudflare: Verified by the Green Web Foundation
Info::
Cloudflare: 100% renewable energy for global network since 2019
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 CloudflareCDN Cloudflare

Cloudflare: Verified by the Green Web Foundation

Cloudflare: 100% renewable energy for global network since 2019

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 27 KB (vs 4208 KB first visit). 226 of 228 resources are served from browser cache, saving 0.97g CO2 per repeat visit.
Info::
Repeat visit: 0.01g CO2 (first visit: 0.97g)
First visit
4208 KB
Repeat visit
27 KB

99% reduction on repeat visits

Saving 0.97g CO2 per returning visitor

226 resources served from cache · 2 resources re-downloaded

A+
Green Hosting
Whether the site is served from green-energy infrastructure
PASS

Green Hosting

This site is hosted on green energy infrastructure

Provider: Cloudflare

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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