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https://siteworth.co

Sustainability

· 8 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
4
INFO
1
Checks
8
4 PASS 2 REVIEW 1 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 Apache HTTP ServerCDN Not identified

Based on known provider commitments. Verify at thegreenwebfoundation.org

B
Transfer Efficiency
82% efficient
REVIEW
82% efficient
Info::
Transfer efficiency: 82%
An estimated 185 KB (18%) could be eliminated: 0 KB via better compression, 0 KB via modern image formats, 185 KB of unused JavaScript. This wasted data produces 0.05g of unnecessary CO2 per page view.
82% efficient

Total waste: 185 KB (18% of page weight)

Unused JS 185 KB

0.05g unnecessary CO2 per visit

Actual transfer 1041 KB
Theoretical minimum 855 KB
Potential savings 185 KB (0.05g 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
CO2 Per Page Load
0.29g CO2 per view
PASS
0.29g CO2 per view
Info::
0.29g CO2 per page view
This page transfers 1.0 MB, producing an estimated 0.29g of CO2 per visit using the Sustainable Web Design model (v4). Breakdown: data center 0.05g, network 0.05g, end-user device 0.18g.
Got: 0.29g CO2 Expected: < 0.50g (sustainability target)
Info::
At 10,000 monthly views: 34.6 kg CO2/year
With 10,000 page views per month, this page would generate approximately 34.6 kg of CO2 annually — equivalent to charging 4320 smartphones.

0.29g

Carbon Footprint per page view

Below sustainability target (0.50g)

Cleaner than 82% of websites

Sustainable Web Design model v4 · Page size: 1.0 MB

Your site
0.29g
Top 10%
0.20g
Target
0.50g
Median website
0.60g

Energy Breakdown

Data center
0.05g
Network
0.05g
End-user device
0.18g
At 10,000 monthly views: Monthly: 2.9 kg · Annual: 34.6 kg · ≈ 4320 smartphone charges
A+
Repeat Visit Weight
95% cached
PASS
95% cached
Info::
95% reduction on repeat visits
Returning visitors download only 54 KB (vs 1041 KB first visit). 50 of 56 resources are served from browser cache, saving 0.27g CO2 per repeat visit.
Info::
Repeat visit: 0.02g CO2 (first visit: 0.29g)
First visit
1041 KB
Repeat visit
54 KB

95% reduction on repeat visits

Saving 0.27g CO2 per returning visitor

50 resources served from cache · 6 resources re-downloaded

A
Carbon Budget
18th percentile
PASS
18th percentile
Info::
0.29g CO2 — below the sustainability target of 0.50g
Cleaner than an estimated 82% of websites analyzed. This page meets the Web Sustainability Guidelines target.
Info::
Estimated 18th percentile
Compared to: top 10% = 0.20g, target = 0.50g, median = 0.60g per page view.
Top 10%
Target
Median website

0.29g

18th percentile

Cleaner than 82% of websites

Below the Web Sustainability Guidelines target

vs Median 52% cleaner ✓
vs Target 42% cleaner ✓
A+
Web Font Weight Variants
2 font weights loaded across 2 famil(y/ies) -- reasonable
PASS
2 font weights loaded across 2 famil(y/ies) -- reasonable
Info::
2 font weight(s) loaded across 2 famil(y/ies)
Image Optimization
10 images, 254 KB total, 0 KB wasted
INFO

Image Optimization Audit

Total Images

10

Total Size

254 KB

10 missing dimensions 9 missing lazy loading
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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