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https://rs-online.com

Sustainability

· 6 checks — CO2 emissions, green hosting, repeat-visit weight, carbon budget, and transfer efficiency rolled into one auditable list.
SCORE
78
GRADE
C
FIX
1
REVIEW
2
PASS
3
INFO
0
Device:
Mobile Desktop
Checks
6
3 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::
Akamai: Committed to 50% renewable by 2030
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 Akamai✗

Akamai: Committed to 50% renewable by 2030

Based on known provider commitments. Verify at thegreenwebfoundation.org

B
Transfer Efficiency
85% efficient
REVIEW
85% efficient
Info::
Transfer efficiency: 85%
An estimated 151 KB (15%) could be eliminated: 0 KB via better compression, 0 KB via modern image formats, 151 KB of unused JavaScript. This wasted data produces 0.04g of unnecessary CO2 per page view.
85% efficient

Total waste: 151 KB (15% of page weight)

Unused JS 151 KB

0.04g unnecessary CO2 per visit

Actual transfer 997 KB
Theoretical minimum 845 KB
Potential savings 151 KB (0.04g 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
0.28g CO2 per view
PASS
0.28g CO2 per view
Info::
0.28g CO2 per page view
This page transfers 1.0 MB, producing an estimated 0.28g 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: 0.28g CO2 Expected: < 0.50g (sustainability target)
Info::
At 10,000 monthly views: 33.1 kg CO2/year
With 10,000 page views per month, this page would generate approximately 33.1 kg of CO2 annually — equivalent to charging 4136 smartphones.

0.28g

Carbon Footprint per page view

✓ Below sustainability target (0.50g)

Cleaner than 83% of websites

Sustainable Web Design model v4 · Page size: 1.0 MB

Your site
0.28g
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: 2.8 kg · Annual: 33.1 kg · ≈ 4136 smartphone charges
A+
Repeat Visit Weight
97% cached
PASS
97% cached
Info::
97% reduction on repeat visits
Returning visitors download only 28 KB (vs 997 KB first visit). 39 of 40 resources are served from browser cache, saving 0.27g CO2 per repeat visit.
Info::
Repeat visit: 0.01g CO2 (first visit: 0.28g)
First visit
997 KB
Repeat visit
28 KB

97% reduction on repeat visits

Saving 0.27g CO2 per returning visitor

39 resources served from cache · 1 resources re-downloaded

A
Carbon Budget
17th percentile
PASS
17th percentile
Info::
0.28g CO2 — below the sustainability target of 0.50g
Cleaner than an estimated 83% of websites analyzed. This page meets the Web Sustainability Guidelines target.
Info::
Estimated 17th percentile
Compared to: top 10% = 0.20g, target = 0.50g, median = 0.60g per page view.
Top 10%
Target
Median website

0.28g

17th percentile

Cleaner than 83% of websites

✓ Below the Web Sustainability Guidelines target

vs Median 54% cleaner ✓
vs Target 45% cleaner ✓
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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