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https://jezebel.com

Sustainability

· 6 checks — CO2 emissions, green hosting, repeat-visit weight, carbon budget, and transfer efficiency rolled into one auditable list.
SCORE
90
GRADE
A
FIX
0
REVIEW
1
PASS
5
INFO
0
Device:
Mobile Desktop
Checks
6
5 PASS 1 REVIEW
B
Transfer Efficiency
88% efficient
REVIEW
88% efficient
Info::
Transfer efficiency: 88%
An estimated 210 KB (12%) could be eliminated: 0 KB via better compression, 0 KB via modern image formats, 210 KB of unused JavaScript. This wasted data produces 0.05g of unnecessary CO2 per page view.
88% efficient

Total waste: 210 KB (12% of page weight)

Unused JS 210 KB

0.05g unnecessary CO2 per visit

Actual transfer 1751 KB
Theoretical minimum 1540 KB
Potential savings 210 KB (0.05g CO2)

See Deep Analysis sections above for specific optimizations.

A
CO2 Per Page Load
0.40g CO2 per view
PASS
0.40g CO2 per view
Info::
0.40g CO2 per page view
This page transfers 1.7 MB, producing an estimated 0.40g of CO2 per visit using the Sustainable Web Design model (v4). Breakdown: data center 0.01g, network 0.08g, end-user device 0.31g.
Got: 0.40g CO2 Expected: < 0.50g (sustainability target)
Info::
At 10,000 monthly views: 48.6 kg CO2/year
With 10,000 page views per month, this page would generate approximately 48.6 kg of CO2 annually — equivalent to charging 6071 smartphones.
Info::
Green hosting reduces data center emissions

0.40g

Carbon Footprint per page view

✓ Below sustainability target (0.50g)

Cleaner than 70% of websites

Sustainable Web Design model v4 · Page size: 1.7 MB

Your site
0.40g
Top 10%
0.20g
Target
0.50g
Median website
0.60g

Energy Breakdown

Data center
0.01g
Network
0.08g
End-user device
0.31g
At 10,000 monthly views: Monthly: 4.0 kg · Annual: 48.6 kg · ≈ 6071 smartphone charges
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
98% cached
PASS
98% cached
Info::
98% reduction on repeat visits
Returning visitors download only 41 KB (vs 1751 KB first visit). 76 of 77 resources are served from browser cache, saving 0.40g CO2 per repeat visit.
Info::
Repeat visit: 0.01g CO2 (first visit: 0.40g)
First visit
1751 KB
Repeat visit
41 KB

98% reduction on repeat visits

Saving 0.40g CO2 per returning visitor

76 resources served from cache · 1 resources re-downloaded

A
Carbon Budget
30th percentile
PASS
30th percentile
Info::
0.40g CO2 — below the sustainability target of 0.50g
Cleaner than an estimated 70% of websites analyzed. This page meets the Web Sustainability Guidelines target.
Info::
Estimated 30th percentile
Compared to: top 10% = 0.20g, target = 0.50g, median = 0.60g per page view.
Top 10%
Target
Median website

0.40g

30th percentile

Cleaner than 70% of websites

✓ Below the Web Sustainability Guidelines target

vs Median 33% cleaner ✓
vs Target 19% cleaner ✓
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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