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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
Device:
Mobile Desktop
Checks
6
3 PASS 1 REVIEW 2 FIX
D
CO2 Per Page Load
Action
1.36g CO2 per view
FIX
1.36g CO2 per view
Warning::
1.36g CO2 per page view
This page transfers 5.7 MB, producing an estimated 1.36g of CO2 per visit using the Sustainable Web Design model (v4). Breakdown: data center 0.03g, network 0.28g, end-user device 1.05g.
Got: 1.36g CO2 Expected: < 0.50g (sustainability target)
Info::
At 10,000 monthly views: 163.3 kg CO2/year
With 10,000 page views per month, this page would generate approximately 163.3 kg of CO2 annually — equivalent to charging 20407 smartphones.
Info::
Green hosting reduces data center emissions

1.36g

Carbon Footprint per page view

✗ Above sustainability target (0.50g)

Cleaner than 29% of websites

Sustainable Web Design model v4 · Page size: 5.7 MB

Your site
1.36g
Top 10%
0.20g
Target
0.50g
Median website
0.60g

Energy Breakdown

Data center
0.03g
Network
0.28g
End-user device
1.05g
At 10,000 monthly views: Monthly: 13.6 kg · Annual: 163.3 kg · ≈ 20407 smartphone charges
F
Carbon Budget
Action
71th percentile
FIX
71th percentile
Warning::
1.36g CO2 — above the median website (0.60g)
Heavier than an estimated 29% of websites. Reducing page weight, optimizing images, and removing unused JavaScript would lower the carbon footprint. See the Performance tab.
Info::
Estimated 71th percentile
Compared to: top 10% = 0.20g, target = 0.50g, median = 0.60g per page view.
Top 10%
Target
Median website

1.36g

71st percentile

Cleaner than 29% of websites

✗ Above the median website

vs Median 127% more
vs Target 172% more
C
Transfer Efficiency
Action
75% efficient
REVIEW
75% efficient
Warning::
Transfer efficiency: 75%
An estimated 1471 KB (25%) could be eliminated: 0 KB via better compression, 0 KB via modern image formats, 1471 KB of unused JavaScript. This wasted data produces 0.34g of unnecessary CO2 per page view.
75% efficient

Total waste: 1471 KB (25% of page weight)

Unused JS 1471 KB

0.34g unnecessary CO2 per visit

Actual transfer 5885 KB
Theoretical minimum 4414 KB
Potential savings 1471 KB (0.34g 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 Cloudflare✓CDN 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 49 KB (vs 5885 KB first visit). 106 of 112 resources are served from browser cache, saving 1.35g CO2 per repeat visit.
Info::
Repeat visit: 0.01g CO2 (first visit: 1.36g)
First visit
5885 KB
Repeat visit
49 KB

99% reduction on repeat visits

Saving 1.35g CO2 per returning visitor

106 resources served from cache · 6 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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