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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
81
GRADE
B
FIX
1
REVIEW
2
PASS
3
INFO
0
Device:
Mobile Desktop
Checks
6
3 PASS 2 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

B
Carbon Budget
39th percentile
REVIEW
39th percentile
Info::
0.49g CO2 — below the sustainability target of 0.50g
Cleaner than an estimated 61% of websites analyzed. This page meets the Web Sustainability Guidelines target.
Info::
Estimated 39th percentile
Compared to: top 10% = 0.20g, target = 0.50g, median = 0.60g per page view.
Top 10%
Target
Median website

0.49g

39th percentile

Cleaner than 61% of websites

✓ Below the Web Sustainability Guidelines target

vs Median 18% cleaner ✓
vs Target 1% cleaner ✓
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
0.49g CO2 per view
PASS
0.49g CO2 per view
Info::
0.49g CO2 per page view
This page transfers 1.7 MB, producing an estimated 0.49g of CO2 per visit using the Sustainable Web Design model (v4). Breakdown: data center 0.09g, network 0.09g, end-user device 0.32g.
Got: 0.49g CO2 Expected: < 0.50g (sustainability target)
Info::
At 10,000 monthly views: 59.3 kg CO2/year
With 10,000 page views per month, this page would generate approximately 59.3 kg of CO2 annually — equivalent to charging 7413 smartphones.

0.49g

Carbon Footprint per page view

✓ Below sustainability target (0.50g)

Cleaner than 61% of websites

Sustainable Web Design model v4 · Page size: 1.7 MB

Your site
0.49g
Top 10%
0.20g
Target
0.50g
Median website
0.60g

Energy Breakdown

Data center
0.09g
Network
0.09g
End-user device
0.32g
At 10,000 monthly views: Monthly: 4.9 kg · Annual: 59.3 kg · ≈ 7413 smartphone charges
A+
Repeat Visit Weight
99% cached
PASS
99% cached
Info::
99% reduction on repeat visits
Returning visitors download only 22 KB (vs 1787 KB first visit). 25 of 26 resources are served from browser cache, saving 0.49g CO2 per repeat visit.
Info::
Repeat visit: 0.01g CO2 (first visit: 0.49g)
First visit
1787 KB
Repeat visit
22 KB

99% reduction on repeat visits

Saving 0.49g CO2 per returning visitor

25 resources served from cache · 1 resources re-downloaded

A+
Transfer Efficiency
97% efficient
PASS
97% efficient
Info::
Transfer efficiency: 97%
Only 57 KB of potential savings identified. Your page is well-optimized for size.
97% efficient

Total waste: 57 KB (3% of page weight)

Unused JS 57 KB

0.02g unnecessary CO2 per visit

Actual transfer 1787 KB
Theoretical minimum 1729 KB
Potential savings 57 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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