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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
1.06g CO2 per view
FIX
1.06g CO2 per view
Warning::
1.06g CO2 per page view
This page transfers 4.5 MB, producing an estimated 1.06g of CO2 per visit using the Sustainable Web Design model (v4). Breakdown: data center 0.03g, network 0.22g, end-user device 0.82g.
Got: 1.06g CO2 Expected: < 0.50g (sustainability target)
Info::
At 10,000 monthly views: 127.7 kg CO2/year
With 10,000 page views per month, this page would generate approximately 127.7 kg of CO2 annually — equivalent to charging 15960 smartphones.
Info::
Green hosting reduces data center emissions

1.06g

Carbon Footprint per page view

Above sustainability target (0.50g)

Cleaner than 37% of websites

Sustainable Web Design model v4 · Page size: 4.5 MB

Your site
1.06g
Top 10%
0.20g
Target
0.50g
Median website
0.60g

Energy Breakdown

Data center
0.03g
Network
0.22g
End-user device
0.82g
At 10,000 monthly views: Monthly: 10.6 kg · Annual: 127.7 kg · ≈ 15960 smartphone charges
D
Carbon Budget
Action
63th percentile
FIX
63th percentile
Warning::
1.06g CO2 — above the median website (0.60g)
Heavier than an estimated 37% of websites. Reducing page weight, optimizing images, and removing unused JavaScript would lower the carbon footprint. See the Performance tab.
Info::
Estimated 63th percentile
Compared to: top 10% = 0.20g, target = 0.50g, median = 0.60g per page view.
Top 10%
Target
Median website

1.06g

63rd percentile

Cleaner than 37% of websites

Above the median website

vs Median 77% more
vs Target 113% more
B
Transfer Efficiency
84% efficient
REVIEW
84% efficient
Info::
Transfer efficiency: 84%
An estimated 727 KB (16%) could be eliminated: 0 KB via better compression, 0 KB via modern image formats, 727 KB of unused JavaScript. This wasted data produces 0.17g of unnecessary CO2 per page view.
84% efficient

Total waste: 727 KB (16% of page weight)

Unused JS 727 KB

0.17g unnecessary CO2 per visit

Actual transfer 4603 KB
Theoretical minimum 3875 KB
Potential savings 727 KB (0.17g 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 4603 KB first visit). 229 of 231 resources are served from browser cache, saving 1.06g CO2 per repeat visit.
Info::
Repeat visit: 0.01g CO2 (first visit: 1.06g)
First visit
4603 KB
Repeat visit
27 KB

99% reduction on repeat visits

Saving 1.06g CO2 per returning visitor

229 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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