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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
62
GRADE
D
FIX
2
REVIEW
1
PASS
3
INFO
0
Device:
Mobile Desktop
Checks
6
3 PASS 1 REVIEW 2 FIX
F
CO2 Per Page Load
Action
4.25g CO2 per view
FIX
4.25g CO2 per view
Critical::
4.25g CO2 per page view
This page transfers 18.0 MB, producing an estimated 4.25g of CO2 per visit using the Sustainable Web Design model (v4). Breakdown: data center 0.11g, network 0.88g, end-user device 3.27g.
Got: 4.25g CO2 Expected: < 0.50g (sustainability target)
Info::
At 10,000 monthly views: 510.1 kg CO2/year
With 10,000 page views per month, this page would generate approximately 510.1 kg of CO2 annually — equivalent to charging 63761 smartphones.
Info::
Green hosting reduces data center emissions

4.25g

Carbon Footprint per page view

✗ Above sustainability target (0.50g)

Cleaner than 5% of websites

Sustainable Web Design model v4 · Page size: 18.0 MB

Your site
4.25g
Top 10%
0.20g
Target
0.50g
Median website
0.60g

Energy Breakdown

Data center
0.11g
Network
0.88g
End-user device
3.27g
At 10,000 monthly views: Monthly: 42.5 kg · Annual: 510.1 kg · ≈ 63761 smartphone charges
F
Carbon Budget
Action
95th percentile
FIX
95th percentile
Warning::
4.25g CO2 — above the median website (0.60g)
Heavier than an estimated 5% of websites. Reducing page weight, optimizing images, and removing unused JavaScript would lower the carbon footprint. See the Performance tab.
Info::
Estimated 95th percentile
Compared to: top 10% = 0.20g, target = 0.50g, median = 0.60g per page view.
Top 10%
Target
Median website

4.25g

95th percentile

Cleaner than 5% of websites

✗ Above the median website

vs Median 608% more
vs Target 750% 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

A+
Repeat Visit Weight
92% cached
PASS
92% cached
Info::
92% reduction on repeat visits
Returning visitors download only 1435 KB (vs 18390 KB first visit). 369 of 400 resources are served from browser cache, saving 3.92g CO2 per repeat visit.
Info::
Repeat visit: 0.33g CO2 (first visit: 4.25g)
First visit
18390 KB
Repeat visit
1435 KB

92% reduction on repeat visits

Saving 3.92g CO2 per returning visitor

369 resources served from cache · 31 resources re-downloaded

A+
Transfer Efficiency
99% efficient
PASS
99% efficient
Info::
Transfer efficiency: 99%
Only 173 KB of potential savings identified. Your page is well-optimized for size.
99% efficient

Total waste: 173 KB (1% of page weight)

Unused JS 173 KB

0.04g unnecessary CO2 per visit

Actual transfer 18390 KB
Theoretical minimum 18217 KB
Potential savings 173 KB (0.04g CO2)

See Deep Analysis sections above for specific optimizations.

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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