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https://sonarsource.com

Sustainability

· 6 checks — CO2 emissions, green hosting, repeat-visit weight, carbon budget, and transfer efficiency rolled into one auditable list.
SCORE
73
GRADE
C
FIX
2
REVIEW
2
PASS
2
INFO
0
Device:
Mobile Desktop
Checks
6
2 PASS 2 REVIEW 2 FIX
D
CO2 Per Page Load
Action
0.84g CO2 per view
FIX
0.84g CO2 per view
Info::
0.84g CO2 per page view
This page transfers 3.5 MB, producing an estimated 0.84g of CO2 per visit using the Sustainable Web Design model (v4). Breakdown: data center 0.02g, network 0.17g, end-user device 0.64g.
Got: 0.84g CO2 Expected: < 0.50g (sustainability target)
Info::
At 10,000 monthly views: 100.7 kg CO2/year
With 10,000 page views per month, this page would generate approximately 100.7 kg of CO2 annually — equivalent to charging 12590 smartphones.
Info::
Green hosting reduces data center emissions

0.84g

Carbon Footprint per page view

✗ Above sustainability target (0.50g)

Cleaner than 44% of websites

Sustainable Web Design model v4 · Page size: 3.5 MB

Your site
0.84g
Top 10%
0.20g
Target
0.50g
Median website
0.60g

Energy Breakdown

Data center
0.02g
Network
0.17g
End-user device
0.64g
At 10,000 monthly views: Monthly: 8.4 kg · Annual: 100.7 kg · ≈ 12590 smartphone charges
D
Carbon Budget
Action
56th percentile
FIX
56th percentile
Warning::
0.84g CO2 — above the median website (0.60g)
Heavier than an estimated 44% of websites. Reducing page weight, optimizing images, and removing unused JavaScript would lower the carbon footprint. See the Performance tab.
Info::
Estimated 56th percentile
Compared to: top 10% = 0.20g, target = 0.50g, median = 0.60g per page view.
Top 10%
Target
Median website

0.84g

56th percentile

Cleaner than 44% of websites

✗ Above the median website

vs Median 40% more
vs Target 68% more
B
Transfer Efficiency
82% efficient
REVIEW
82% efficient
Info::
Transfer efficiency: 82%
An estimated 652 KB (18%) could be eliminated: 0 KB via better compression, 0 KB via modern image formats, 652 KB of unused JavaScript. This wasted data produces 0.15g of unnecessary CO2 per page view.
82% efficient

Total waste: 652 KB (18% of page weight)

Unused JS 652 KB

0.15g unnecessary CO2 per visit

Actual transfer 3631 KB
Theoretical minimum 2978 KB
Potential savings 652 KB (0.15g 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
Green Hosting
Green (cdn)
PASS
Green (cdn)
Info::
Netlify CDN uses renewable energy
Since most traffic is served through the CDN, the majority of data transfer energy is renewable.
Info::
Netlify: Hosted on AWS/Google Cloud with renewable energy matching
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 Not identified✗CDN Netlify✓

Netlify: Hosted on AWS/Google Cloud with renewable energy matching

Based on known provider commitments. Verify at thegreenwebfoundation.org

A+
Repeat Visit Weight
99% cached
PASS
99% cached
Info::
99% reduction on repeat visits
Returning visitors download only 46 KB (vs 3631 KB first visit). 171 of 172 resources are served from browser cache, saving 0.83g CO2 per repeat visit.
Info::
Repeat visit: 0.01g CO2 (first visit: 0.84g)
First visit
3631 KB
Repeat visit
46 KB

99% reduction on repeat visits

Saving 0.83g CO2 per returning visitor

171 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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