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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
90
GRADE
A
FIX
1
REVIEW
1
PASS
4
INFO
0
Checks
6
4 PASS 1 REVIEW 1 FIX
D
Green Hosting
Action
Unknown
FIX
Unknown
Info::
Hosting provider could not be identified
Without knowing the provider, we cannot determine their energy sourcing. Check with your hosting provider about their renewable energy commitments.
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 HostingUnable to Determine
Hosting Not identifiedCDN Not identified

Based on known provider commitments. Verify at thegreenwebfoundation.org

C
Green Hosting
Action
Whether the site is served from green-energy infrastructure
REVIEW

Green Hosting

No green hosting detected

A+
CO2 Per Page Load
0.14g CO2 per view
PASS
0.14g CO2 per view
Info::
0.14g CO2 per page view
This page transfers 0.5 MB, producing an estimated 0.14g of CO2 per visit using the Sustainable Web Design model (v4). Breakdown: data center 0.03g, network 0.02g, end-user device 0.09g.
Got: 0.14g CO2 Expected: < 0.50g (sustainability target)
Info::
At 10,000 monthly views: 16.9 kg CO2/year
With 10,000 page views per month, this page would generate approximately 16.9 kg of CO2 annually — equivalent to charging 2118 smartphones.

0.14g

Carbon Footprint per page view

Below sustainability target (0.50g)

Cleaner than 90% of websites

Sustainable Web Design model v4 · Page size: 0.5 MB

Your site
0.14g
Top 10%
0.20g
Target
0.50g
Median website
0.60g

Energy Breakdown

Data center
0.03g
Network
0.02g
End-user device
0.09g
At 10,000 monthly views: Monthly: 1.4 kg · Annual: 16.9 kg · ≈ 2118 smartphone charges
A+
Repeat Visit Weight
81% cached
PASS
81% cached
Info::
81% reduction on repeat visits
Returning visitors download only 96 KB (vs 510 KB first visit). 21 of 23 resources are served from browser cache, saving 0.11g CO2 per repeat visit.
Info::
Repeat visit: 0.03g CO2 (first visit: 0.14g)
First visit
510 KB
Repeat visit
96 KB

81% reduction on repeat visits

Saving 0.11g CO2 per returning visitor

21 resources served from cache · 2 resources re-downloaded

A+
Carbon Budget
10th percentile
PASS
10th percentile
Info::
0.14g CO2 — below the sustainability target of 0.50g
Cleaner than an estimated 90% of websites analyzed. This page meets the Web Sustainability Guidelines target.
Info::
Estimated 10th percentile
Compared to: top 10% = 0.20g, target = 0.50g, median = 0.60g per page view.
Top 10%
Target
Median website

0.14g

10th percentile

Cleaner than 90% of websites

Below the Web Sustainability Guidelines target

vs Median 76% cleaner ✓
vs Target 72% cleaner ✓
A+
Transfer Efficiency
100% efficient
PASS
100% efficient
Info::
Transfer efficiency: 100%
Only 0 KB of potential savings identified. Your page is well-optimized for size.
100% efficient
Actual transfer 510 KB
Theoretical minimum 510 KB

See Deep Analysis sections above for specific optimizations.

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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