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Sustainability

· 6 checks — CO2 emissions, green hosting, repeat-visit weight, carbon budget, and transfer efficiency rolled into one auditable list.
SCORE
72
GRADE
C
FIX
2
REVIEW
2
PASS
2
INFO
0
Device:
Mobile Desktop
Checks
6
2 PASS 2 REVIEW 2 FIX
F
CO2 Per Page Load
Action
1.54g CO2 per view
FIX
1.54g CO2 per view
Warning::
1.54g CO2 per page view
This page transfers 6.5 MB, producing an estimated 1.54g of CO2 per visit using the Sustainable Web Design model (v4). Breakdown: data center 0.04g, network 0.32g, end-user device 1.18g.
Got: 1.54g CO2 Expected: < 0.50g (sustainability target)
Info::
At 10,000 monthly views: 185.1 kg CO2/year
With 10,000 page views per month, this page would generate approximately 185.1 kg of CO2 annually — equivalent to charging 23134 smartphones.
Info::
Green hosting reduces data center emissions

1.54g

Carbon Footprint per page view

✗ Above sustainability target (0.50g)

Cleaner than 24% of websites

Sustainable Web Design model v4 · Page size: 6.5 MB

Your site
1.54g
Top 10%
0.20g
Target
0.50g
Median website
0.60g

Energy Breakdown

Data center
0.04g
Network
0.32g
End-user device
1.18g
At 10,000 monthly views: Monthly: 15.4 kg · Annual: 185.1 kg · ≈ 23134 smartphone charges
F
Carbon Budget
Action
76th percentile
FIX
76th percentile
Warning::
1.54g CO2 — above the median website (0.60g)
Heavier than an estimated 24% of websites. Reducing page weight, optimizing images, and removing unused JavaScript would lower the carbon footprint. See the Performance tab.
Info::
Estimated 76th percentile
Compared to: top 10% = 0.20g, target = 0.50g, median = 0.60g per page view.
Top 10%
Target
Median website

1.54g

76th percentile

Cleaner than 24% of websites

✗ Above the median website

vs Median 157% more
vs Target 208% more
B
Green Hosting
Green (hosting)
REVIEW
Green (hosting)
Info::
Next.js uses renewable energy
Info::
Next.js: 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 Next.js✓CDN Not identified✗

Next.js: Verified by the Green Web Foundation

Based on known provider commitments. Verify at thegreenwebfoundation.org

B
Transfer Efficiency
86% efficient
REVIEW
86% efficient
Info::
Transfer efficiency: 86%
An estimated 911 KB (14%) could be eliminated: 0 KB via better compression, 0 KB via modern image formats, 911 KB of unused JavaScript. This wasted data produces 0.21g of unnecessary CO2 per page view.
86% efficient

Total waste: 911 KB (14% of page weight)

Unused JS 911 KB

0.21g unnecessary CO2 per visit

Actual transfer 6672 KB
Theoretical minimum 5760 KB
Potential savings 911 KB (0.21g CO2)

See Deep Analysis sections above for specific optimizations.

A+
Repeat Visit Weight
95% cached
PASS
95% cached
Info::
95% reduction on repeat visits
Returning visitors download only 327 KB (vs 6672 KB first visit). 108 of 109 resources are served from browser cache, saving 1.47g CO2 per repeat visit.
Info::
Repeat visit: 0.08g CO2 (first visit: 1.54g)
First visit
6672 KB
Repeat visit
327 KB

95% reduction on repeat visits

Saving 1.47g CO2 per returning visitor

108 resources served from cache · 1 resources re-downloaded

A+
Green Hosting
Whether the site is served from green-energy infrastructure
PASS

Green Hosting

This site is hosted on green energy infrastructure

Provider: Hetzner Online GmbH

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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