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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
1.10g CO2 per view
FIX
1.10g CO2 per view
Warning::
1.10g CO2 per page view
This page transfers 4.6 MB, producing an estimated 1.10g of CO2 per visit using the Sustainable Web Design model (v4). Breakdown: data center 0.03g, network 0.23g, end-user device 0.84g.
Got: 1.10g CO2 Expected: < 0.50g (sustainability target)
Info::
At 10,000 monthly views: 131.5 kg CO2/year
With 10,000 page views per month, this page would generate approximately 131.5 kg of CO2 annually — equivalent to charging 16438 smartphones.
Info::
Green hosting reduces data center emissions

1.10g

Carbon Footprint per page view

✗ Above sustainability target (0.50g)

Cleaner than 36% of websites

Sustainable Web Design model v4 · Page size: 4.6 MB

Your site
1.10g
Top 10%
0.20g
Target
0.50g
Median website
0.60g

Energy Breakdown

Data center
0.03g
Network
0.23g
End-user device
0.84g
At 10,000 monthly views: Monthly: 11.0 kg · Annual: 131.5 kg · ≈ 16438 smartphone charges
D
Carbon Budget
Action
64th percentile
FIX
64th percentile
Warning::
1.10g CO2 — above the median website (0.60g)
Heavier than an estimated 36% of websites. Reducing page weight, optimizing images, and removing unused JavaScript would lower the carbon footprint. See the Performance tab.
Info::
Estimated 64th percentile
Compared to: top 10% = 0.20g, target = 0.50g, median = 0.60g per page view.
Top 10%
Target
Median website

1.10g

64th percentile

Cleaner than 36% of websites

✗ Above the median website

vs Median 83% more
vs Target 119% 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::
Google Cloud CDN: Inherits Google Cloud regional renewable mix
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 Google Cloud CDN✗

Google Cloud: Verified by the Green Web Foundation

Google Cloud CDN: Inherits Google Cloud regional renewable mix

Based on known provider commitments. Verify at thegreenwebfoundation.org

B
Transfer Efficiency
80% efficient
REVIEW
80% efficient
Info::
Transfer efficiency: 80%
An estimated 941 KB (20%) could be eliminated: 0 KB via better compression, 0 KB via modern image formats, 941 KB of unused JavaScript. This wasted data produces 0.22g of unnecessary CO2 per page view.
80% efficient

Total waste: 941 KB (20% of page weight)

Unused JS 941 KB

0.22g unnecessary CO2 per visit

Actual transfer 4741 KB
Theoretical minimum 3799 KB
Potential savings 941 KB (0.22g CO2)

See Deep Analysis sections above for specific optimizations.

A+
Repeat Visit Weight
99% cached
PASS
99% cached
Info::
99% reduction on repeat visits
Returning visitors download only 57 KB (vs 4741 KB first visit). 130 of 132 resources are served from browser cache, saving 1.08g CO2 per repeat visit.
Info::
Repeat visit: 0.01g CO2 (first visit: 1.10g)
First visit
4741 KB
Repeat visit
57 KB

99% reduction on repeat visits

Saving 1.08g CO2 per returning visitor

130 resources served from cache · 2 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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