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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
72
GRADE
C
FIX
2
REVIEW
2
PASS
2
INFO
0
Device:
Mobile Desktop
Checks
6
2 PASS 2 REVIEW 2 FIX
D
CO2 Per Page Load
Action
1.00g CO2 per view
FIX
1.00g CO2 per view
Warning::
1.00g CO2 per page view
This page transfers 4.2 MB, producing an estimated 1.00g of CO2 per visit using the Sustainable Web Design model (v4). Breakdown: data center 0.03g, network 0.21g, end-user device 0.77g.
Got: 1.00g CO2 Expected: < 0.50g (sustainability target)
Info::
At 10,000 monthly views: 120.1 kg CO2/year
With 10,000 page views per month, this page would generate approximately 120.1 kg of CO2 annually — equivalent to charging 15012 smartphones.
Info::
Green hosting reduces data center emissions

1.00g

Carbon Footprint per page view

✗ Above sustainability target (0.50g)

Cleaner than 39% of websites

Sustainable Web Design model v4 · Page size: 4.2 MB

Your site
1.00g
Top 10%
0.20g
Target
0.50g
Median website
0.60g

Energy Breakdown

Data center
0.03g
Network
0.21g
End-user device
0.77g
At 10,000 monthly views: Monthly: 10.0 kg · Annual: 120.1 kg · ≈ 15012 smartphone charges
D
Carbon Budget
Action
61th percentile
FIX
61th percentile
Warning::
1.00g CO2 — above the median website (0.60g)
Heavier than an estimated 39% of websites. Reducing page weight, optimizing images, and removing unused JavaScript would lower the carbon footprint. See the Performance tab.
Info::
Estimated 61th percentile
Compared to: top 10% = 0.20g, target = 0.50g, median = 0.60g per page view.
Top 10%
Target
Median website

1.00g

61st percentile

Cleaner than 39% of websites

✗ Above the median website

vs Median 67% more
vs Target 100% more
B
Green Hosting
Green (hosting)
REVIEW
Green (hosting)
Info::
Google Cloud uses renewable energy
Info::
Google Cloud: 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 Google Cloud✓CDN Not identified✗

Google Cloud: Verified by the Green Web Foundation

Based on known provider commitments. Verify at thegreenwebfoundation.org

B
Transfer Efficiency
85% efficient
REVIEW
85% efficient
Info::
Transfer efficiency: 85%
An estimated 630 KB (15%) could be eliminated: 0 KB via better compression, 0 KB via modern image formats, 630 KB of unused JavaScript. This wasted data produces 0.15g of unnecessary CO2 per page view.
85% efficient

Total waste: 630 KB (15% of page weight)

Unused JS 630 KB

0.15g unnecessary CO2 per visit

Actual transfer 4330 KB
Theoretical minimum 3699 KB
Potential savings 630 KB (0.15g CO2)

See Deep Analysis sections above for specific optimizations.

A+
Repeat Visit Weight
98% cached
PASS
98% cached
Info::
98% reduction on repeat visits
Returning visitors download only 81 KB (vs 4330 KB first visit). 120 of 124 resources are served from browser cache, saving 0.98g CO2 per repeat visit.
Info::
Repeat visit: 0.02g CO2 (first visit: 1.00g)
First visit
4330 KB
Repeat visit
81 KB

98% reduction on repeat visits

Saving 0.98g CO2 per returning visitor

120 resources served from cache · 4 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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