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https://jacobin.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
1.31g CO2 per view
FIX
1.31g CO2 per view
Warning::
1.31g CO2 per page view
This page transfers 5.5 MB, producing an estimated 1.31g of CO2 per visit using the Sustainable Web Design model (v4). Breakdown: data center 0.03g, network 0.27g, end-user device 1.00g.
Got: 1.31g CO2 Expected: < 0.50g (sustainability target)
Info::
At 10,000 monthly views: 156.8 kg CO2/year
With 10,000 page views per month, this page would generate approximately 156.8 kg of CO2 annually — equivalent to charging 19602 smartphones.
Info::
Green hosting reduces data center emissions

1.31g

Carbon Footprint per page view

Above sustainability target (0.50g)

Cleaner than 30% of websites

Sustainable Web Design model v4 · Page size: 5.5 MB

Your site
1.31g
Top 10%
0.20g
Target
0.50g
Median website
0.60g

Energy Breakdown

Data center
0.03g
Network
0.27g
End-user device
1.00g
At 10,000 monthly views: Monthly: 13.1 kg · Annual: 156.8 kg · ≈ 19602 smartphone charges
D
Carbon Budget
Action
70th percentile
FIX
70th percentile
Warning::
1.31g CO2 — above the median website (0.60g)
Heavier than an estimated 30% of websites. Reducing page weight, optimizing images, and removing unused JavaScript would lower the carbon footprint. See the Performance tab.
Info::
Estimated 70th percentile
Compared to: top 10% = 0.20g, target = 0.50g, median = 0.60g per page view.
Top 10%
Target
Median website

1.31g

70th percentile

Cleaner than 30% of websites

Above the median website

vs Median 118% more
vs Target 161% more
B
Transfer Efficiency
76% efficient
REVIEW
76% efficient
Info::
Transfer efficiency: 76%
An estimated 1367 KB (24%) could be eliminated: 0 KB via better compression, 0 KB via modern image formats, 1367 KB of unused JavaScript. This wasted data produces 0.32g of unnecessary CO2 per page view.
76% efficient

Total waste: 1367 KB (24% of page weight)

Unused JS 1367 KB

0.32g unnecessary CO2 per visit

Actual transfer 5653 KB
Theoretical minimum 4286 KB
Potential savings 1367 KB (0.32g 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 46 KB (vs 5653 KB first visit). 79 of 83 resources are served from browser cache, saving 1.30g CO2 per repeat visit.
Info::
Repeat visit: 0.01g CO2 (first visit: 1.31g)
First visit
5653 KB
Repeat visit
46 KB

99% reduction on repeat visits

Saving 1.30g CO2 per returning visitor

79 resources served from cache · 4 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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