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https://esteri.it

Sustainability

· 6 checks — CO2 emissions, green hosting, repeat-visit weight, carbon budget, and transfer efficiency rolled into one auditable list.
SCORE
74
GRADE
C
FIX
1
REVIEW
4
PASS
1
INFO
0
Device:
Mobile Desktop
Checks
6
1 PASS 4 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
CO2 Per Page Load
0.57g CO2 per view
REVIEW
0.57g CO2 per view
Info::
0.57g CO2 per page view
This page transfers 2.0 MB, producing an estimated 0.57g of CO2 per visit using the Sustainable Web Design model (v4). Breakdown: data center 0.11g, network 0.10g, end-user device 0.37g.
Got: 0.57g CO2 Expected: < 0.50g (sustainability target)
Info::
At 10,000 monthly views: 68.9 kg CO2/year
With 10,000 page views per month, this page would generate approximately 68.9 kg of CO2 annually — equivalent to charging 8611 smartphones.

0.57g

Carbon Footprint per page view

✗ Above sustainability target (0.50g)

Cleaner than 53% of websites

Sustainable Web Design model v4 · Page size: 2.0 MB

Your site
0.57g
Top 10%
0.20g
Target
0.50g
Median website
0.60g

Energy Breakdown

Data center
0.11g
Network
0.10g
End-user device
0.37g
At 10,000 monthly views: Monthly: 5.7 kg · Annual: 68.9 kg · ≈ 8611 smartphone charges
B
Carbon Budget
47th percentile
REVIEW
47th percentile
Info::
0.57g CO2 — below the median website (0.60g)
Better than an estimated 53% of websites, but above the sustainability target of 0.50g. Reducing page weight would help reach the target.
Info::
Estimated 47th percentile
Compared to: top 10% = 0.20g, target = 0.50g, median = 0.60g per page view.
Top 10%
Target
Median website

0.57g

47th percentile

Cleaner than 53% of websites

✗ Above the median website

vs Median 4% cleaner ✓
vs Target 15% more
B
Transfer Efficiency
87% efficient
REVIEW
87% efficient
Info::
Transfer efficiency: 87%
An estimated 279 KB (13%) could be eliminated: 0 KB via better compression, 0 KB via modern image formats, 279 KB of unused JavaScript. This wasted data produces 0.08g of unnecessary CO2 per page view.
87% efficient

Total waste: 279 KB (13% of page weight)

Unused JS 279 KB

0.08g unnecessary CO2 per visit

Actual transfer 2075 KB
Theoretical minimum 1796 KB
Potential savings 279 KB (0.08g CO2)

See Deep Analysis sections above for specific optimizations.

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

Green Hosting

No green hosting detected

A+
Repeat Visit Weight
99% cached
PASS
99% cached
Info::
99% reduction on repeat visits
Returning visitors download only 24 KB (vs 2075 KB first visit). 49 of 50 resources are served from browser cache, saving 0.57g CO2 per repeat visit.
Info::
Repeat visit: 0.01g CO2 (first visit: 0.57g)
First visit
2075 KB
Repeat visit
24 KB

99% reduction on repeat visits

Saving 0.57g CO2 per returning visitor

49 resources served from cache · 1 resources re-downloaded

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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