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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
3
PASS
3
INFO
0
Device:
Mobile Desktop
Checks
6
3 PASS 3 REVIEW
B
Green Hosting
Green (hosting)
REVIEW
Green (hosting)
Info::
Amazon Web Services uses renewable energy
Info::
Amazon Web Services: Verified by the Green Web Foundation
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 Amazon Web Services✓CDN Not identified✗

Amazon Web Services: Verified by the Green Web Foundation

Based on known provider commitments. Verify at thegreenwebfoundation.org

B
Carbon Budget
34th percentile
REVIEW
34th percentile
Info::
0.45g CO2 — below the sustainability target of 0.50g
Cleaner than an estimated 66% of websites analyzed. This page meets the Web Sustainability Guidelines target.
Info::
Estimated 34th percentile
Compared to: top 10% = 0.20g, target = 0.50g, median = 0.60g per page view.
Top 10%
Target
Median website

0.45g

34th percentile

Cleaner than 66% of websites

✓ Below the Web Sustainability Guidelines target

vs Median 25% cleaner ✓
vs Target 10% cleaner ✓
B
Transfer Efficiency
83% efficient
REVIEW
83% efficient
Info::
Transfer efficiency: 83%
An estimated 332 KB (17%) could be eliminated: 0 KB via better compression, 0 KB via modern image formats, 332 KB of unused JavaScript. This wasted data produces 0.08g of unnecessary CO2 per page view.
83% efficient

Total waste: 332 KB (17% of page weight)

Unused JS 332 KB

0.08g unnecessary CO2 per visit

Actual transfer 1942 KB
Theoretical minimum 1609 KB
Potential savings 332 KB (0.08g CO2)

See Deep Analysis sections above for specific optimizations.

A
CO2 Per Page Load
0.45g CO2 per view
PASS
0.45g CO2 per view
Info::
0.45g CO2 per page view
This page transfers 1.9 MB, producing an estimated 0.45g of CO2 per visit using the Sustainable Web Design model (v4). Breakdown: data center 0.01g, network 0.09g, end-user device 0.34g.
Got: 0.45g CO2 Expected: < 0.50g (sustainability target)
Info::
At 10,000 monthly views: 53.9 kg CO2/year
With 10,000 page views per month, this page would generate approximately 53.9 kg of CO2 annually — equivalent to charging 6733 smartphones.
Info::
Green hosting reduces data center emissions

0.45g

Carbon Footprint per page view

✓ Below sustainability target (0.50g)

Cleaner than 66% of websites

Sustainable Web Design model v4 · Page size: 1.9 MB

Your site
0.45g
Top 10%
0.20g
Target
0.50g
Median website
0.60g

Energy Breakdown

Data center
0.01g
Network
0.09g
End-user device
0.34g
At 10,000 monthly views: Monthly: 4.5 kg · Annual: 53.9 kg · ≈ 6733 smartphone charges
A+
Repeat Visit Weight
83% cached
PASS
83% cached
Info::
83% reduction on repeat visits
Returning visitors download only 329 KB (vs 1942 KB first visit). 127 of 130 resources are served from browser cache, saving 0.37g CO2 per repeat visit.
Info::
Repeat visit: 0.08g CO2 (first visit: 0.45g)
First visit
1942 KB
Repeat visit
329 KB

83% reduction on repeat visits

Saving 0.37g CO2 per returning visitor

127 resources served from cache · 3 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: Google Cloud

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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