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https://stores.jp

Sustainability

· 6 checks — CO2 emissions, green hosting, repeat-visit weight, carbon budget, and transfer efficiency rolled into one auditable list.
SCORE
57
GRADE
D
FIX
3
REVIEW
1
PASS
2
INFO
0
Device:
Mobile Desktop
Checks
6
2 PASS 1 REVIEW 3 FIX
F
CO2 Per Page Load
Action
2.54g CO2 per view
FIX
2.54g CO2 per view
Critical::
2.54g CO2 per page view
This page transfers 9.0 MB, producing an estimated 2.54g of CO2 per visit using the Sustainable Web Design model (v4). Breakdown: data center 0.47g, network 0.44g, end-user device 1.63g.
Got: 2.54g CO2 Expected: < 0.50g (sustainability target)
Info::
At 10,000 monthly views: 305.3 kg CO2/year
With 10,000 page views per month, this page would generate approximately 305.3 kg of CO2 annually — equivalent to charging 38164 smartphones.

2.54g

Carbon Footprint per page view

✗ Above sustainability target (0.50g)

Cleaner than 5% of websites

Sustainable Web Design model v4 · Page size: 9.0 MB

Your site
2.54g
Top 10%
0.20g
Target
0.50g
Median website
0.60g

Energy Breakdown

Data center
0.47g
Network
0.44g
End-user device
1.63g
At 10,000 monthly views: Monthly: 25.4 kg · Annual: 305.3 kg · ≈ 38164 smartphone charges
D
Green Hosting
Action
Not green
FIX
Not green
Info::
No confirmed renewable energy commitment detected
Consider providers like Cloudflare, Google Cloud, or Vercel that match 100% of their energy use with renewables.
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 HostingNot Green Hosted
Hosting Next.js✗CDN Not identified✗

Based on known provider commitments. Verify at thegreenwebfoundation.org

F
Carbon Budget
Action
95th percentile
FIX
95th percentile
Warning::
2.54g CO2 — above the median website (0.60g)
Heavier than an estimated 5% of websites. Reducing page weight, optimizing images, and removing unused JavaScript would lower the carbon footprint. See the Performance tab.
Info::
Estimated 95th percentile
Compared to: top 10% = 0.20g, target = 0.50g, median = 0.60g per page view.
Top 10%
Target
Median website

2.54g

95th percentile

Cleaner than 5% of websites

✗ Above the median website

vs Median 324% more
vs Target 409% more
C
Green Hosting
Action
Whether the site is served from green-energy infrastructure
REVIEW

Green Hosting

No green hosting detected

A+
Repeat Visit Weight
100% cached
PASS
100% cached
Info::
100% reduction on repeat visits
Returning visitors download only 22 KB (vs 9199 KB first visit). 128 of 129 resources are served from browser cache, saving 2.54g CO2 per repeat visit.
Info::
Repeat visit: 0.01g CO2 (first visit: 2.54g)
First visit
9199 KB
Repeat visit
22 KB

100% reduction on repeat visits

Saving 2.54g CO2 per returning visitor

128 resources served from cache · 1 resources re-downloaded

A+
Transfer Efficiency
93% efficient
PASS
93% efficient
Info::
Transfer efficiency: 93%
Only 620 KB of potential savings identified. Your page is well-optimized for size.
93% efficient

Total waste: 620 KB (7% of page weight)

Unused JS 620 KB

0.17g unnecessary CO2 per visit

Actual transfer 9199 KB
Theoretical minimum 8579 KB
Potential savings 620 KB (0.17g 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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