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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
84
GRADE
B
FIX
1
REVIEW
1
PASS
4
INFO
0
Device:
Mobile Desktop
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 identified✗CDN 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
0.25g CO2 per view
PASS
0.25g CO2 per view
Info::
0.25g CO2 per page view
This page transfers 0.9 MB, producing an estimated 0.25g of CO2 per visit using the Sustainable Web Design model (v4). Breakdown: data center 0.05g, network 0.04g, end-user device 0.16g.
Got: 0.25g CO2 Expected: < 0.50g (sustainability target)
Info::
At 10,000 monthly views: 30.4 kg CO2/year
With 10,000 page views per month, this page would generate approximately 30.4 kg of CO2 annually — equivalent to charging 3805 smartphones.

0.25g

Carbon Footprint per page view

✓ Below sustainability target (0.50g)

Cleaner than 85% of websites

Sustainable Web Design model v4 · Page size: 0.9 MB

Your site
0.25g
Top 10%
0.20g
Target
0.50g
Median website
0.60g

Energy Breakdown

Data center
0.05g
Network
0.04g
End-user device
0.16g
At 10,000 monthly views: Monthly: 2.5 kg · Annual: 30.4 kg · ≈ 3805 smartphone charges
A+
Repeat Visit Weight
93% cached
PASS
93% cached
Info::
93% reduction on repeat visits
Returning visitors download only 65 KB (vs 917 KB first visit). 39 of 40 resources are served from browser cache, saving 0.24g CO2 per repeat visit.
Info::
Repeat visit: 0.02g CO2 (first visit: 0.25g)
First visit
917 KB
Repeat visit
65 KB

93% reduction on repeat visits

Saving 0.24g CO2 per returning visitor

39 resources served from cache · 1 resources re-downloaded

A
Carbon Budget
15th percentile
PASS
15th percentile
Info::
0.25g CO2 — below the sustainability target of 0.50g
Cleaner than an estimated 85% of websites analyzed. This page meets the Web Sustainability Guidelines target.
Info::
Estimated 15th percentile
Compared to: top 10% = 0.20g, target = 0.50g, median = 0.60g per page view.
Top 10%
Target
Median website

0.25g

15th percentile

Cleaner than 85% of websites

✓ Below the Web Sustainability Guidelines target

vs Median 58% cleaner ✓
vs Target 49% cleaner ✓
A+
Transfer Efficiency
93% efficient
PASS
93% efficient
Info::
Transfer efficiency: 93%
Only 63 KB of potential savings identified. Your page is well-optimized for size.
93% efficient

Total waste: 63 KB (7% of page weight)

Unused JS 63 KB

0.02g unnecessary CO2 per visit

Actual transfer 917 KB
Theoretical minimum 853 KB
Potential savings 63 KB (0.02g CO2)

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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