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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
89% efficient
REVIEW
89% efficient
Info::
Transfer efficiency: 89%
An estimated 132 KB (11%) could be eliminated: 0 KB via better compression, 0 KB via modern image formats, 132 KB of unused JavaScript. This wasted data produces 0.03g of unnecessary CO2 per page view.
89% efficient

Total waste: 132 KB (11% of page weight)

Unused JS 132 KB

0.03g unnecessary CO2 per visit

Actual transfer 1231 KB
Theoretical minimum 1098 KB
Potential savings 132 KB (0.03g CO2)

See Deep Analysis sections above for specific optimizations.

A
CO2 Per Page Load
0.28g CO2 per view
PASS
0.28g CO2 per view
Info::
0.28g CO2 per page view
This page transfers 1.2 MB, producing an estimated 0.28g of CO2 per visit using the Sustainable Web Design model (v4). Breakdown: data center 0.01g, network 0.06g, end-user device 0.22g.
Got: 0.28g CO2 Expected: < 0.50g (sustainability target)
Info::
At 10,000 monthly views: 34.2 kg CO2/year
With 10,000 page views per month, this page would generate approximately 34.2 kg of CO2 annually — equivalent to charging 4269 smartphones.
Info::
Green hosting reduces data center emissions

0.28g

Carbon Footprint per page view

✓ Below sustainability target (0.50g)

Cleaner than 82% of websites

Sustainable Web Design model v4 · Page size: 1.2 MB

Your site
0.28g
Top 10%
0.20g
Target
0.50g
Median website
0.60g

Energy Breakdown

Data center
0.01g
Network
0.06g
End-user device
0.22g
At 10,000 monthly views: Monthly: 2.8 kg · Annual: 34.2 kg · ≈ 4269 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
84% cached
PASS
84% cached
Info::
84% reduction on repeat visits
Returning visitors download only 196 KB (vs 1231 KB first visit). 80 of 82 resources are served from browser cache, saving 0.24g CO2 per repeat visit.
Info::
Repeat visit: 0.05g CO2 (first visit: 0.28g)
First visit
1231 KB
Repeat visit
196 KB

84% reduction on repeat visits

Saving 0.24g CO2 per returning visitor

80 resources served from cache · 2 resources re-downloaded

A
Carbon Budget
18th percentile
PASS
18th percentile
Info::
0.28g CO2 — below the sustainability target of 0.50g
Cleaner than an estimated 82% of websites analyzed. This page meets the Web Sustainability Guidelines target.
Info::
Estimated 18th percentile
Compared to: top 10% = 0.20g, target = 0.50g, median = 0.60g per page view.
Top 10%
Target
Median website

0.28g

18th percentile

Cleaner than 82% of websites

✓ Below the Web Sustainability Guidelines target

vs Median 53% cleaner ✓
vs Target 43% 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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