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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
83
GRADE
B
FIX
0
REVIEW
2
PASS
4
INFO
0
Device:
Mobile Desktop
Checks
6
4 PASS 2 REVIEW
B
Carbon Budget
32th percentile
REVIEW
32th percentile
Info::
0.42g CO2 — below the sustainability target of 0.50g
Cleaner than an estimated 68% of websites analyzed. This page meets the Web Sustainability Guidelines target.
Info::
Estimated 32th percentile
Compared to: top 10% = 0.20g, target = 0.50g, median = 0.60g per page view.
Top 10%
Target
Median website

0.42g

32nd percentile

Cleaner than 68% of websites

✓ Below the Web Sustainability Guidelines target

vs Median 30% cleaner ✓
vs Target 16% cleaner ✓
C
Transfer Efficiency
Action
63% efficient
REVIEW
63% efficient
Warning::
Transfer efficiency: 63%
An estimated 665 KB (37%) could be eliminated: 0 KB via better compression, 0 KB via modern image formats, 665 KB of unused JavaScript. This wasted data produces 0.15g of unnecessary CO2 per page view.
63% efficient

Total waste: 665 KB (37% of page weight)

Unused JS 665 KB

0.15g unnecessary CO2 per visit

Actual transfer 1817 KB
Theoretical minimum 1152 KB
Potential savings 665 KB (0.15g CO2)

See Deep Analysis sections above for specific optimizations.

A
CO2 Per Page Load
0.42g CO2 per view
PASS
0.42g CO2 per view
Info::
0.42g CO2 per page view
This page transfers 1.8 MB, producing an estimated 0.42g of CO2 per visit using the Sustainable Web Design model (v4). Breakdown: data center 0.01g, network 0.09g, end-user device 0.32g.
Got: 0.42g CO2 Expected: < 0.50g (sustainability target)
Info::
At 10,000 monthly views: 50.4 kg CO2/year
With 10,000 page views per month, this page would generate approximately 50.4 kg of CO2 annually — equivalent to charging 6302 smartphones.
Info::
Green hosting reduces data center emissions

0.42g

Carbon Footprint per page view

✓ Below sustainability target (0.50g)

Cleaner than 68% of websites

Sustainable Web Design model v4 · Page size: 1.8 MB

Your site
0.42g
Top 10%
0.20g
Target
0.50g
Median website
0.60g

Energy Breakdown

Data center
0.01g
Network
0.09g
End-user device
0.32g
At 10,000 monthly views: Monthly: 4.2 kg · Annual: 50.4 kg · ≈ 6302 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 35 KB (vs 1817 KB first visit). 74 of 75 resources are served from browser cache, saving 0.41g CO2 per repeat visit.
Info::
Repeat visit: 0.01g CO2 (first visit: 0.42g)
First visit
1817 KB
Repeat visit
35 KB

98% reduction on repeat visits

Saving 0.41g CO2 per returning visitor

74 resources served from cache · 1 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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