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https://jugem.jp

Sustainability

· 6 checks — CO2 emissions, green hosting, repeat-visit weight, carbon budget, and transfer efficiency rolled into one auditable list.
SCORE
70
GRADE
C
FIX
2
REVIEW
3
PASS
1
INFO
0
Device:
Mobile Desktop
Checks
6
1 PASS 3 REVIEW 2 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

D
Carbon Budget
Action
52th percentile
FIX
52th percentile
Warning::
0.70g CO2 — above the median website (0.60g)
Heavier than an estimated 48% of websites. Reducing page weight, optimizing images, and removing unused JavaScript would lower the carbon footprint. See the Performance tab.
Info::
Estimated 52th percentile
Compared to: top 10% = 0.20g, target = 0.50g, median = 0.60g per page view.
Top 10%
Target
Median website

0.70g

52nd percentile

Cleaner than 48% of websites

✗ Above the median website

vs Median 17% more
vs Target 40% more
B
CO2 Per Page Load
0.70g CO2 per view
REVIEW
0.70g CO2 per view
Info::
0.70g CO2 per page view
This page transfers 2.5 MB, producing an estimated 0.70g of CO2 per visit using the Sustainable Web Design model (v4). Breakdown: data center 0.13g, network 0.12g, end-user device 0.45g.
Got: 0.70g CO2 Expected: < 0.50g (sustainability target)
Info::
At 10,000 monthly views: 84.2 kg CO2/year
With 10,000 page views per month, this page would generate approximately 84.2 kg of CO2 annually — equivalent to charging 10521 smartphones.

0.70g

Carbon Footprint per page view

✗ Above sustainability target (0.50g)

Cleaner than 48% of websites

Sustainable Web Design model v4 · Page size: 2.5 MB

Your site
0.70g
Top 10%
0.20g
Target
0.50g
Median website
0.60g

Energy Breakdown

Data center
0.13g
Network
0.12g
End-user device
0.45g
At 10,000 monthly views: Monthly: 7.0 kg · Annual: 84.2 kg · ≈ 10521 smartphone charges
B
Transfer Efficiency
83% efficient
REVIEW
83% efficient
Info::
Transfer efficiency: 83%
An estimated 443 KB (17%) could be eliminated: 0 KB via better compression, 0 KB via modern image formats, 443 KB of unused JavaScript. This wasted data produces 0.12g of unnecessary CO2 per page view.
83% efficient

Total waste: 443 KB (17% of page weight)

Unused JS 443 KB

0.12g unnecessary CO2 per visit

Actual transfer 2536 KB
Theoretical minimum 2093 KB
Potential savings 443 KB (0.12g 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 16 KB (vs 2536 KB first visit). 122 of 125 resources are served from browser cache, saving 0.70g CO2 per repeat visit.
Info::
Repeat visit: 0.00g CO2 (first visit: 0.70g)
First visit
2536 KB
Repeat visit
16 KB

99% reduction on repeat visits

Saving 0.70g CO2 per returning visitor

122 resources served from cache · 3 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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