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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
78
GRADE
C
FIX
1
REVIEW
1
PASS
4
INFO
0
Device:
Mobile Desktop
Checks
6
4 PASS 1 REVIEW 1 FIX
D
Transfer Efficiency
Action
54% efficient
FIX
54% efficient
Warning::
Transfer efficiency: 54%
An estimated 598 KB (46%) could be eliminated: 0 KB via better compression, 0 KB via modern image formats, 598 KB of unused JavaScript. This wasted data produces 0.14g of unnecessary CO2 per page view.
54% efficient

Total waste: 598 KB (46% of page weight)

Unused JS 598 KB

0.14g unnecessary CO2 per visit

Actual transfer 1302 KB
Theoretical minimum 703 KB
Potential savings 598 KB (0.14g CO2)

See Deep Analysis sections above for specific optimizations.

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
CO2 Per Page Load
0.30g CO2 per view
PASS
0.30g CO2 per view
Info::
0.30g CO2 per page view
This page transfers 1.3 MB, producing an estimated 0.30g of CO2 per visit using the Sustainable Web Design model (v4). Breakdown: data center 0.01g, network 0.06g, end-user device 0.23g.
Got: 0.30g CO2 Expected: < 0.50g (sustainability target)
Info::
At 10,000 monthly views: 36.1 kg CO2/year
With 10,000 page views per month, this page would generate approximately 36.1 kg of CO2 annually — equivalent to charging 4514 smartphones.
Info::
Green hosting reduces data center emissions

0.30g

Carbon Footprint per page view

✓ Below sustainability target (0.50g)

Cleaner than 80% of websites

Sustainable Web Design model v4 · Page size: 1.3 MB

Your site
0.30g
Top 10%
0.20g
Target
0.50g
Median website
0.60g

Energy Breakdown

Data center
0.01g
Network
0.06g
End-user device
0.23g
At 10,000 monthly views: Monthly: 3.0 kg · Annual: 36.1 kg · ≈ 4514 smartphone charges
A+
Repeat Visit Weight
95% cached
PASS
95% cached
Info::
95% reduction on repeat visits
Returning visitors download only 65 KB (vs 1302 KB first visit). 77 of 79 resources are served from browser cache, saving 0.29g CO2 per repeat visit.
Info::
Repeat visit: 0.02g CO2 (first visit: 0.30g)
First visit
1302 KB
Repeat visit
65 KB

95% reduction on repeat visits

Saving 0.29g CO2 per returning visitor

77 resources served from cache · 2 resources re-downloaded

A
Carbon Budget
20th percentile
PASS
20th percentile
Info::
0.30g CO2 — below the sustainability target of 0.50g
Cleaner than an estimated 80% of websites analyzed. This page meets the Web Sustainability Guidelines target.
Info::
Estimated 20th percentile
Compared to: top 10% = 0.20g, target = 0.50g, median = 0.60g per page view.
Top 10%
Target
Median website

0.30g

20th percentile

Cleaner than 80% of websites

✓ Below the Web Sustainability Guidelines target

vs Median 50% cleaner ✓
vs Target 40% cleaner ✓
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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