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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
0.33g CO2 per view
PASS
0.33g CO2 per view
Info::
0.33g CO2 per page view
This page transfers 1.2 MB, producing an estimated 0.33g of CO2 per visit using the Sustainable Web Design model (v4). Breakdown: data center 0.06g, network 0.06g, end-user device 0.21g.
Got: 0.33g CO2 Expected: < 0.50g (sustainability target)
Info::
At 10,000 monthly views: 39.1 kg CO2/year
With 10,000 page views per month, this page would generate approximately 39.1 kg of CO2 annually — equivalent to charging 4893 smartphones.

0.33g

Carbon Footprint per page view

✓ Below sustainability target (0.50g)

Cleaner than 78% of websites

Sustainable Web Design model v4 · Page size: 1.2 MB

Your site
0.33g
Top 10%
0.20g
Target
0.50g
Median website
0.60g

Energy Breakdown

Data center
0.06g
Network
0.06g
End-user device
0.21g
At 10,000 monthly views: Monthly: 3.3 kg · Annual: 39.1 kg · ≈ 4893 smartphone charges
A+
Repeat Visit Weight
98% cached
PASS
98% cached
Info::
98% reduction on repeat visits
Returning visitors download only 20 KB (vs 1179 KB first visit). 45 of 46 resources are served from browser cache, saving 0.32g CO2 per repeat visit.
Info::
Repeat visit: 0.01g CO2 (first visit: 0.33g)
First visit
1179 KB
Repeat visit
20 KB

98% reduction on repeat visits

Saving 0.32g CO2 per returning visitor

45 resources served from cache · 1 resources re-downloaded

A
Carbon Budget
22th percentile
PASS
22th percentile
Info::
0.33g CO2 — below the sustainability target of 0.50g
Cleaner than an estimated 78% of websites analyzed. This page meets the Web Sustainability Guidelines target.
Info::
Estimated 22th percentile
Compared to: top 10% = 0.20g, target = 0.50g, median = 0.60g per page view.
Top 10%
Target
Median website

0.33g

22nd percentile

Cleaner than 78% of websites

✓ Below the Web Sustainability Guidelines target

vs Median 46% cleaner ✓
vs Target 35% cleaner ✓
A+
Transfer Efficiency
93% efficient
PASS
93% efficient
Info::
Transfer efficiency: 93%
Only 86 KB of potential savings identified. Your page is well-optimized for size.
93% efficient

Total waste: 86 KB (7% of page weight)

Unused JS 86 KB

0.02g unnecessary CO2 per visit

Actual transfer 1179 KB
Theoretical minimum 1092 KB
Potential savings 86 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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