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https://lrb.co.uk

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
1
REVIEW
3
PASS
2
INFO
0
Device:
Mobile Desktop
Checks
6
2 PASS 3 REVIEW 1 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

B
Carbon Budget
38th percentile
REVIEW
38th percentile
Info::
0.49g CO2 — below the sustainability target of 0.50g
Cleaner than an estimated 62% of websites analyzed. This page meets the Web Sustainability Guidelines target.
Info::
Estimated 38th percentile
Compared to: top 10% = 0.20g, target = 0.50g, median = 0.60g per page view.
Top 10%
Target
Median website

0.49g

38th percentile

Cleaner than 62% of websites

✓ Below the Web Sustainability Guidelines target

vs Median 19% cleaner ✓
vs Target 2% cleaner ✓
C
Transfer Efficiency
Action
65% efficient
REVIEW
65% efficient
Warning::
Transfer efficiency: 65%
An estimated 626 KB (35%) could be eliminated: 0 KB via better compression, 0 KB via modern image formats, 626 KB of unused JavaScript. This wasted data produces 0.17g of unnecessary CO2 per page view.
65% efficient

Total waste: 626 KB (35% of page weight)

Unused JS 626 KB

0.17g unnecessary CO2 per visit

Actual transfer 1768 KB
Theoretical minimum 1141 KB
Potential savings 626 KB (0.17g 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
0.49g CO2 per view
PASS
0.49g CO2 per view
Info::
0.49g CO2 per page view
This page transfers 1.7 MB, producing an estimated 0.49g of CO2 per visit using the Sustainable Web Design model (v4). Breakdown: data center 0.09g, network 0.08g, end-user device 0.31g.
Got: 0.49g CO2 Expected: < 0.50g (sustainability target)
Info::
At 10,000 monthly views: 58.7 kg CO2/year
With 10,000 page views per month, this page would generate approximately 58.7 kg of CO2 annually — equivalent to charging 7334 smartphones.

0.49g

Carbon Footprint per page view

✓ Below sustainability target (0.50g)

Cleaner than 62% of websites

Sustainable Web Design model v4 · Page size: 1.7 MB

Your site
0.49g
Top 10%
0.20g
Target
0.50g
Median website
0.60g

Energy Breakdown

Data center
0.09g
Network
0.08g
End-user device
0.31g
At 10,000 monthly views: Monthly: 4.9 kg · Annual: 58.7 kg · ≈ 7334 smartphone charges
A+
Repeat Visit Weight
94% cached
PASS
94% cached
Info::
94% reduction on repeat visits
Returning visitors download only 112 KB (vs 1768 KB first visit). 42 of 44 resources are served from browser cache, saving 0.46g CO2 per repeat visit.
Info::
Repeat visit: 0.03g CO2 (first visit: 0.49g)
First visit
1768 KB
Repeat visit
112 KB

94% reduction on repeat visits

Saving 0.46g CO2 per returning visitor

42 resources served from cache · 2 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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