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https://kuleuven.be

Sustainability

· 6 checks — CO2 emissions, green hosting, repeat-visit weight, carbon budget, and transfer efficiency rolled into one auditable list.
SCORE
74
GRADE
C
FIX
1
REVIEW
4
PASS
1
INFO
0
Checks
6
1 PASS 4 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 identifiedCDN Not identified

Based on known provider commitments. Verify at thegreenwebfoundation.org

B
CO2 Per Page Load
0.58g CO2 per view
REVIEW
0.58g CO2 per view
Info::
0.58g CO2 per page view
This page transfers 2.0 MB, producing an estimated 0.58g of CO2 per visit using the Sustainable Web Design model (v4). Breakdown: data center 0.11g, network 0.10g, end-user device 0.37g.
Got: 0.58g CO2 Expected: < 0.50g (sustainability target)
Info::
At 10,000 monthly views: 69.2 kg CO2/year
With 10,000 page views per month, this page would generate approximately 69.2 kg of CO2 annually — equivalent to charging 8654 smartphones.

0.58g

Carbon Footprint per page view

Above sustainability target (0.50g)

Cleaner than 53% of websites

Sustainable Web Design model v4 · Page size: 2.0 MB

Your site
0.58g
Top 10%
0.20g
Target
0.50g
Median website
0.60g

Energy Breakdown

Data center
0.11g
Network
0.10g
End-user device
0.37g
At 10,000 monthly views: Monthly: 5.8 kg · Annual: 69.2 kg · ≈ 8654 smartphone charges
B
Carbon Budget
47th percentile
REVIEW
47th percentile
Info::
0.58g CO2 — below the median website (0.60g)
Better than an estimated 53% of websites, but above the sustainability target of 0.50g. Reducing page weight would help reach the target.
Info::
Estimated 47th percentile
Compared to: top 10% = 0.20g, target = 0.50g, median = 0.60g per page view.
Top 10%
Target
Median website

0.58g

47th percentile

Cleaner than 53% of websites

Above the median website

vs Median 4% cleaner ✓
vs Target 15% more
B
Transfer Efficiency
77% efficient
REVIEW
77% efficient
Info::
Transfer efficiency: 77%
An estimated 475 KB (23%) could be eliminated: 0 KB via better compression, 0 KB via modern image formats, 475 KB of unused JavaScript. This wasted data produces 0.13g of unnecessary CO2 per page view.
77% efficient

Total waste: 475 KB (23% of page weight)

Unused JS 475 KB

0.13g unnecessary CO2 per visit

Actual transfer 2086 KB
Theoretical minimum 1610 KB
Potential savings 475 KB (0.13g 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+
Repeat Visit Weight
100% cached
PASS
100% cached
Info::
100% reduction on repeat visits
Returning visitors download only 10 KB (vs 2086 KB first visit). 59 of 60 resources are served from browser cache, saving 0.57g CO2 per repeat visit.
Info::
Repeat visit: 0.00g CO2 (first visit: 0.58g)
First visit
2086 KB
Repeat visit
10 KB

100% reduction on repeat visits

Saving 0.57g CO2 per returning visitor

59 resources served from cache · 1 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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