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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
1.07g CO2 per view
FIX
1.07g CO2 per view
Warning::
1.07g CO2 per page view
This page transfers 4.5 MB, producing an estimated 1.07g of CO2 per visit using the Sustainable Web Design model (v4). Breakdown: data center 0.03g, network 0.22g, end-user device 0.82g.
Got: 1.07g CO2 Expected: < 0.50g (sustainability target)
Info::
At 10,000 monthly views: 127.8 kg CO2/year
With 10,000 page views per month, this page would generate approximately 127.8 kg of CO2 annually — equivalent to charging 15977 smartphones.
Info::
Green hosting reduces data center emissions

1.07g

Carbon Footprint per page view

✗ Above sustainability target (0.50g)

Cleaner than 37% of websites

Sustainable Web Design model v4 · Page size: 4.5 MB

Your site
1.07g
Top 10%
0.20g
Target
0.50g
Median website
0.60g

Energy Breakdown

Data center
0.03g
Network
0.22g
End-user device
0.82g
At 10,000 monthly views: Monthly: 10.7 kg · Annual: 127.8 kg · ≈ 15977 smartphone charges
D
Carbon Budget
Action
63th percentile
FIX
63th percentile
Warning::
1.07g CO2 — above the median website (0.60g)
Heavier than an estimated 37% of websites. Reducing page weight, optimizing images, and removing unused JavaScript would lower the carbon footprint. See the Performance tab.
Info::
Estimated 63th percentile
Compared to: top 10% = 0.20g, target = 0.50g, median = 0.60g per page view.
Top 10%
Target
Median website

1.07g

63rd percentile

Cleaner than 37% of websites

✗ Above the median website

vs Median 78% more
vs Target 113% 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
86% efficient
REVIEW
86% efficient
Info::
Transfer efficiency: 86%
An estimated 631 KB (14%) could be eliminated: 0 KB via better compression, 0 KB via modern image formats, 631 KB of unused JavaScript. This wasted data produces 0.15g of unnecessary CO2 per page view.
86% efficient

Total waste: 631 KB (14% of page weight)

Unused JS 631 KB

0.15g unnecessary CO2 per visit

Actual transfer 4608 KB
Theoretical minimum 3977 KB
Potential savings 631 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 4608 KB first visit). 123 of 127 resources are served from browser cache, saving 1.05g CO2 per repeat visit.
Info::
Repeat visit: 0.02g CO2 (first visit: 1.07g)
First visit
4608 KB
Repeat visit
81 KB

98% reduction on repeat visits

Saving 1.05g CO2 per returning visitor

123 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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