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https://imageshack.us

Sustainability

· 6 checks — CO2 emissions, green hosting, repeat-visit weight, carbon budget, and transfer efficiency rolled into one auditable list.
SCORE
63
GRADE
D
FIX
2
REVIEW
2
PASS
2
INFO
0
Device:
Mobile Desktop
Checks
6
2 PASS 2 REVIEW 2 FIX
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 Not identified✗CDN Varnish✗

Based on known provider commitments. Verify at thegreenwebfoundation.org

F
Transfer Efficiency
Action
29% efficient
FIX
29% efficient
Critical::
Transfer efficiency: 29%
An estimated 1063 KB (71%) could be eliminated: 0 KB via better compression, 0 KB via modern image formats, 1063 KB of unused JavaScript. This wasted data produces 0.29g of unnecessary CO2 per page view.
29% efficient

Total waste: 1063 KB (71% of page weight)

Unused JS 1063 KB

0.29g unnecessary CO2 per visit

Actual transfer 1504 KB
Theoretical minimum 440 KB
Potential savings 1063 KB (0.29g CO2)

See Deep Analysis sections above for specific optimizations.

B
Carbon Budget
31th percentile
REVIEW
31th percentile
Info::
0.42g CO2 — below the sustainability target of 0.50g
Cleaner than an estimated 69% of websites analyzed. This page meets the Web Sustainability Guidelines target.
Info::
Estimated 31th percentile
Compared to: top 10% = 0.20g, target = 0.50g, median = 0.60g per page view.
Top 10%
Target
Median website

0.42g

31st percentile

Cleaner than 69% of websites

✓ Below the Web Sustainability Guidelines target

vs Median 31% cleaner ✓
vs Target 17% 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
0.42g CO2 per view
PASS
0.42g CO2 per view
Info::
0.42g CO2 per page view
This page transfers 1.5 MB, producing an estimated 0.42g of CO2 per visit using the Sustainable Web Design model (v4). Breakdown: data center 0.08g, network 0.07g, end-user device 0.27g.
Got: 0.42g CO2 Expected: < 0.50g (sustainability target)
Info::
At 10,000 monthly views: 49.9 kg CO2/year
With 10,000 page views per month, this page would generate approximately 49.9 kg of CO2 annually — equivalent to charging 6241 smartphones.

0.42g

Carbon Footprint per page view

✓ Below sustainability target (0.50g)

Cleaner than 69% of websites

Sustainable Web Design model v4 · Page size: 1.5 MB

Your site
0.42g
Top 10%
0.20g
Target
0.50g
Median website
0.60g

Energy Breakdown

Data center
0.08g
Network
0.07g
End-user device
0.27g
At 10,000 monthly views: Monthly: 4.2 kg · Annual: 49.9 kg · ≈ 6241 smartphone charges
A+
Repeat Visit Weight
98% cached
PASS
98% cached
Info::
98% reduction on repeat visits
Returning visitors download only 32 KB (vs 1504 KB first visit). 30 of 33 resources are served from browser cache, saving 0.41g CO2 per repeat visit.
Info::
Repeat visit: 0.01g CO2 (first visit: 0.42g)
First visit
1504 KB
Repeat visit
32 KB

98% reduction on repeat visits

Saving 0.41g CO2 per returning visitor

30 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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