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https://tenlolisto.com

Sustainability

· 7 checks — CO2 emissions, green hosting, repeat-visit weight, carbon budget, and transfer efficiency rolled into one auditable list.
SCORE
85
GRADE
B
FIX
1
REVIEW
3
PASS
3
INFO
0
Checks
7
3 PASS 3 REVIEW 1 FIX
D
Carbon Budget
Action
52th percentile
FIX
52th percentile
Warning::
0.69g CO2 — above the median website (0.60g)
Heavier than an estimated 48% of websites. Reducing page weight, optimizing images, and removing unused JavaScript would lower the carbon footprint. See the Performance tab.
Info::
Estimated 52th percentile
Compared to: top 10% = 0.20g, target = 0.50g, median = 0.60g per page view.
Top 10%
Target
Median website

0.69g

52nd percentile

Cleaner than 48% of websites

✗ Above the median website

vs Median 14% more
vs Target 37% more
B
CO2 Per Page Load
0.69g CO2 per view
REVIEW
0.69g CO2 per view
Info::
0.69g CO2 per page view
This page transfers 2.9 MB, producing an estimated 0.69g of CO2 per visit using the Sustainable Web Design model (v4). Breakdown: data center 0.02g, network 0.14g, end-user device 0.53g.
Got: 0.69g CO2 Expected: < 0.50g (sustainability target)
Info::
At 10,000 monthly views: 82.3 kg CO2/year
With 10,000 page views per month, this page would generate approximately 82.3 kg of CO2 annually — equivalent to charging 10285 smartphones.
Info::
Green hosting reduces data center emissions

0.69g

Carbon Footprint per page view

✗ Above sustainability target (0.50g)

Cleaner than 48% of websites

Sustainable Web Design model v4 · Page size: 2.9 MB

Your site
0.69g
Top 10%
0.20g
Target
0.50g
Median website
0.60g

Energy Breakdown

Data center
0.02g
Network
0.14g
End-user device
0.53g
At 10,000 monthly views: Monthly: 6.9 kg · Annual: 82.3 kg · ≈ 10285 smartphone charges
B
Web Font Weight Variants
No detectable Google Fonts weights
REVIEW
No detectable Google Fonts weights
Info::
No detectable Google Fonts weights
The analyzer detects font weights via Google Fonts URL parameters (~70% of font-using sites). Self-hosted fonts and non-Google CDN fonts aren't visible to URL-based detection. If you self-host fonts, manually audit how many @font-face weights you ship -- 2-3 weights per family is typically enough; 5+ is usually unused payload.
C
Green Hosting
Action
Whether the site is served from green-energy infrastructure
REVIEW

Green Hosting

No green hosting detected

A+
Green Hosting
Green (both)
PASS
Green (both)
Info::
Both hosting and CDN use renewable energy
Got: Hosting: Vercel, CDN: Vercel
Info::
Vercel: Hosted on AWS/Google Cloud with renewable energy commitments
Info::
Vercel: Hosted on AWS/Google Cloud with 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 Hosting✓ Green Hosted
Hosting Vercel✓CDN Vercel✓

Vercel: Hosted on AWS/Google Cloud with renewable energy commitments

Vercel: Hosted on AWS/Google Cloud with renewable energy commitments

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 17 KB (vs 2966 KB first visit). 95 of 96 resources are served from browser cache, saving 0.68g CO2 per repeat visit.
Info::
Repeat visit: 0.00g CO2 (first visit: 0.69g)
First visit
2966 KB
Repeat visit
17 KB

99% reduction on repeat visits

Saving 0.68g CO2 per returning visitor

95 resources served from cache · 1 resources re-downloaded

A+
Transfer Efficiency
97% efficient
PASS
97% efficient
Info::
Transfer efficiency: 97%
Only 92 KB of potential savings identified. Your page is well-optimized for size.
97% efficient

Total waste: 92 KB (3% of page weight)

Unused JS 92 KB

0.02g unnecessary CO2 per visit

Actual transfer 2966 KB
Theoretical minimum 2873 KB
Potential savings 92 KB (0.02g 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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