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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
1.43g CO2 per view
FIX
1.43g CO2 per view
Warning::
1.43g CO2 per page view
This page transfers 6.0 MB, producing an estimated 1.43g of CO2 per visit using the Sustainable Web Design model (v4). Breakdown: data center 0.04g, network 0.30g, end-user device 1.10g.
Got: 1.43g CO2 Expected: < 0.50g (sustainability target)
Info::
At 10,000 monthly views: 171.4 kg CO2/year
With 10,000 page views per month, this page would generate approximately 171.4 kg of CO2 annually — equivalent to charging 21429 smartphones.
Info::
Green hosting reduces data center emissions

1.43g

Carbon Footprint per page view

✗ Above sustainability target (0.50g)

Cleaner than 27% of websites

Sustainable Web Design model v4 · Page size: 6.0 MB

Your site
1.43g
Top 10%
0.20g
Target
0.50g
Median website
0.60g

Energy Breakdown

Data center
0.04g
Network
0.30g
End-user device
1.10g
At 10,000 monthly views: Monthly: 14.3 kg · Annual: 171.4 kg · ≈ 21429 smartphone charges
F
Carbon Budget
Action
73th percentile
FIX
73th percentile
Warning::
1.43g CO2 — above the median website (0.60g)
Heavier than an estimated 27% of websites. Reducing page weight, optimizing images, and removing unused JavaScript would lower the carbon footprint. See the Performance tab.
Info::
Estimated 73th percentile
Compared to: top 10% = 0.20g, target = 0.50g, median = 0.60g per page view.
Top 10%
Target
Median website

1.43g

73rd percentile

Cleaner than 27% of websites

✗ Above the median website

vs Median 138% more
vs Target 186% 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

C
Transfer Efficiency
Action
70% efficient
REVIEW
70% efficient
Warning::
Transfer efficiency: 70%
An estimated 1825 KB (30%) could be eliminated: 0 KB via better compression, 0 KB via modern image formats, 1825 KB of unused JavaScript. This wasted data produces 0.42g of unnecessary CO2 per page view.
70% efficient

Total waste: 1825 KB (30% of page weight)

Unused JS 1825 KB

0.42g unnecessary CO2 per visit

Actual transfer 6180 KB
Theoretical minimum 4355 KB
Potential savings 1825 KB (0.42g 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 31 KB (vs 6180 KB first visit). 197 of 199 resources are served from browser cache, saving 1.42g CO2 per repeat visit.
Info::
Repeat visit: 0.01g CO2 (first visit: 1.43g)
First visit
6180 KB
Repeat visit
31 KB

99% reduction on repeat visits

Saving 1.42g CO2 per returning visitor

197 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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