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https://lesoir.be

Sustainability

· 6 checks — CO2 emissions, green hosting, repeat-visit weight, carbon budget, and transfer efficiency rolled into one auditable list.
SCORE
60
GRADE
D
FIX
3
REVIEW
1
PASS
2
INFO
0
Device:
Mobile Desktop
Checks
6
2 PASS 1 REVIEW 3 FIX
F
CO2 Per Page Load
Action
1.59g CO2 per view
FIX
1.59g CO2 per view
Warning::
1.59g CO2 per page view
This page transfers 5.6 MB, producing an estimated 1.59g of CO2 per visit using the Sustainable Web Design model (v4). Breakdown: data center 0.29g, network 0.27g, end-user device 1.02g.
Got: 1.59g CO2 Expected: < 0.50g (sustainability target)
Info::
At 10,000 monthly views: 190.2 kg CO2/year
With 10,000 page views per month, this page would generate approximately 190.2 kg of CO2 annually — equivalent to charging 23777 smartphones.

1.59g

Carbon Footprint per page view

✗ Above sustainability target (0.50g)

Cleaner than 22% of websites

Sustainable Web Design model v4 · Page size: 5.6 MB

Your site
1.59g
Top 10%
0.20g
Target
0.50g
Median website
0.60g

Energy Breakdown

Data center
0.29g
Network
0.27g
End-user device
1.02g
At 10,000 monthly views: Monthly: 15.9 kg · Annual: 190.2 kg · ≈ 23777 smartphone charges
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

F
Carbon Budget
Action
78th percentile
FIX
78th percentile
Warning::
1.59g CO2 — above the median website (0.60g)
Heavier than an estimated 22% of websites. Reducing page weight, optimizing images, and removing unused JavaScript would lower the carbon footprint. See the Performance tab.
Info::
Estimated 78th percentile
Compared to: top 10% = 0.20g, target = 0.50g, median = 0.60g per page view.
Top 10%
Target
Median website

1.59g

78th percentile

Cleaner than 22% of websites

✗ Above the median website

vs Median 164% more
vs Target 217% more
C
Green Hosting
Action
Whether the site is served from green-energy infrastructure
REVIEW

Green Hosting

No green hosting detected

A+
Repeat Visit Weight
98% cached
PASS
98% cached
Info::
98% reduction on repeat visits
Returning visitors download only 134 KB (vs 5731 KB first visit). 260 of 265 resources are served from browser cache, saving 1.55g CO2 per repeat visit.
Info::
Repeat visit: 0.04g CO2 (first visit: 1.59g)
First visit
5731 KB
Repeat visit
134 KB

98% reduction on repeat visits

Saving 1.55g CO2 per returning visitor

260 resources served from cache · 5 resources re-downloaded

A+
Transfer Efficiency
93% efficient
PASS
93% efficient
Info::
Transfer efficiency: 93%
Only 411 KB of potential savings identified. Your page is well-optimized for size.
93% efficient

Total waste: 411 KB (7% of page weight)

Unused JS 411 KB

0.11g unnecessary CO2 per visit

Actual transfer 5731 KB
Theoretical minimum 5320 KB
Potential savings 411 KB (0.11g CO2)

See Deep Analysis sections above for specific optimizations.

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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