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https://Svennouwen.nl

Sustainability

· 8 checks — CO2 emissions, green hosting, repeat-visit weight, carbon budget, and transfer efficiency rolled into one auditable list.
SCORE
85
GRADE
B
FIX
0
REVIEW
3
PASS
4
INFO
1
Checks
8
4 PASS 3 REVIEW
B
Green Hosting
Green (hosting)
REVIEW
Green (hosting)
Info::
Combell uses renewable energy
Info::
Combell: Verified by the Green Web Foundation
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 Hosting Green Hosted
Hosting CombellCDN Not identified

Combell: Verified by the Green Web Foundation

Based on known provider commitments. Verify at thegreenwebfoundation.org

C
Transfer Efficiency
Action
68% efficient
REVIEW
68% efficient
Warning::
Transfer efficiency: 68%
An estimated 195 KB (32%) could be eliminated: 0 KB via better compression, 0 KB via modern image formats, 195 KB of unused JavaScript. This wasted data produces 0.05g of unnecessary CO2 per page view.
68% efficient

Total waste: 195 KB (32% of page weight)

Unused JS 195 KB

0.05g unnecessary CO2 per visit

Actual transfer 615 KB
Theoretical minimum 419 KB
Potential savings 195 KB (0.05g CO2)

See Deep Analysis sections above for specific optimizations.

C
Web Font Weight Variants
Action
18 font weights loaded across 1 famil(y/ies)
REVIEW
18 font weights loaded across 1 famil(y/ies)
Warning::
18 font weights loaded -- likely 100+ KB of unused payload
Loading 18 font weights typically transfers 200-400 KB just for fonts. Most pages legitimately use 2-3 weights (regular + bold, maybe medium). Audit which weights your stylesheet actually applies and trim the Google Fonts URL accordingly. Affected families: Plus Jakarta Sans.
A+
CO2 Per Page Load
0.14g CO2 per view
PASS
0.14g CO2 per view
Info::
0.14g CO2 per page view
This page transfers 0.6 MB, producing an estimated 0.14g of CO2 per visit using the Sustainable Web Design model (v4). Breakdown: data center 0.00g, network 0.03g, end-user device 0.11g.
Got: 0.14g CO2 Expected: < 0.50g (sustainability target)
Info::
At 10,000 monthly views: 17.1 kg CO2/year
With 10,000 page views per month, this page would generate approximately 17.1 kg of CO2 annually — equivalent to charging 2133 smartphones.
Info::
Green hosting reduces data center emissions

0.14g

Carbon Footprint per page view

Below sustainability target (0.50g)

Cleaner than 90% of websites

Sustainable Web Design model v4 · Page size: 0.6 MB

Your site
0.14g
Top 10%
0.20g
Target
0.50g
Median website
0.60g

Energy Breakdown

Data center
0.00g
Network
0.03g
End-user device
0.11g
At 10,000 monthly views: Monthly: 1.4 kg · Annual: 17.1 kg · ≈ 2133 smartphone charges
A+
Repeat Visit Weight
97% cached
PASS
97% cached
Info::
97% reduction on repeat visits
Returning visitors download only 16 KB (vs 615 KB first visit). 53 of 54 resources are served from browser cache, saving 0.14g CO2 per repeat visit.
Info::
Repeat visit: 0.00g CO2 (first visit: 0.14g)
First visit
615 KB
Repeat visit
16 KB

97% reduction on repeat visits

Saving 0.14g CO2 per returning visitor

53 resources served from cache · 1 resources re-downloaded

A+
Carbon Budget
10th percentile
PASS
10th percentile
Info::
0.14g CO2 — below the sustainability target of 0.50g
Cleaner than an estimated 90% of websites analyzed. This page meets the Web Sustainability Guidelines target.
Info::
Estimated 10th percentile
Compared to: top 10% = 0.20g, target = 0.50g, median = 0.60g per page view.
Top 10%
Target
Median website

0.14g

10th percentile

Cleaner than 90% of websites

Below the Web Sustainability Guidelines target

vs Median 76% cleaner ✓
vs Target 72% cleaner ✓
A+
Green Hosting
Whether the site is served from green-energy infrastructure
PASS

Green Hosting

This site is hosted on green energy infrastructure

Provider: Combell

Image Optimization
5 images, 54 KB total, 36 KB wasted
INFO

Image Optimization Audit

Total Images

5

Total Size

54 KB

Oversized

2

Wasted

36 KB

3 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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