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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
86
GRADE
B
FIX
0
REVIEW
2
PASS
4
INFO
0
Device:
Mobile Desktop
Checks
6
4 PASS 2 REVIEW
B
Green Hosting
Green (hosting)
REVIEW
Green (hosting)
Info::
Tessellate OS uses renewable energy
Info::
Tessellate OS: 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 Tessellate OS✓CDN Not identified✗

Tessellate OS: Verified by the Green Web Foundation

Based on known provider commitments. Verify at thegreenwebfoundation.org

B
Transfer Efficiency
77% efficient
REVIEW
77% efficient
Info::
Transfer efficiency: 77%
An estimated 248 KB (23%) could be eliminated: 0 KB via better compression, 0 KB via modern image formats, 248 KB of unused JavaScript. This wasted data produces 0.06g of unnecessary CO2 per page view.
77% efficient

Total waste: 248 KB (23% of page weight)

Unused JS 248 KB

0.06g unnecessary CO2 per visit

Actual transfer 1061 KB
Theoretical minimum 813 KB
Potential savings 248 KB (0.06g CO2)

See Deep Analysis sections above for specific optimizations.

A
CO2 Per Page Load
0.25g CO2 per view
PASS
0.25g CO2 per view
Info::
0.25g CO2 per page view
This page transfers 1.0 MB, producing an estimated 0.25g of CO2 per visit using the Sustainable Web Design model (v4). Breakdown: data center 0.01g, network 0.05g, end-user device 0.19g.
Got: 0.25g CO2 Expected: < 0.50g (sustainability target)
Info::
At 10,000 monthly views: 29.4 kg CO2/year
With 10,000 page views per month, this page would generate approximately 29.4 kg of CO2 annually — equivalent to charging 3680 smartphones.
Info::
Green hosting reduces data center emissions

0.25g

Carbon Footprint per page view

✓ Below sustainability target (0.50g)

Cleaner than 86% of websites

Sustainable Web Design model v4 · Page size: 1.0 MB

Your site
0.25g
Top 10%
0.20g
Target
0.50g
Median website
0.60g

Energy Breakdown

Data center
0.01g
Network
0.05g
End-user device
0.19g
At 10,000 monthly views: Monthly: 2.5 kg · Annual: 29.4 kg · ≈ 3680 smartphone charges
A+
Repeat Visit Weight
98% cached
PASS
98% cached
Info::
98% reduction on repeat visits
Returning visitors download only 19 KB (vs 1061 KB first visit). 44 of 45 resources are served from browser cache, saving 0.24g CO2 per repeat visit.
Info::
Repeat visit: 0.00g CO2 (first visit: 0.25g)
First visit
1061 KB
Repeat visit
19 KB

98% reduction on repeat visits

Saving 0.24g CO2 per returning visitor

44 resources served from cache · 1 resources re-downloaded

A
Carbon Budget
14th percentile
PASS
14th percentile
Info::
0.25g CO2 — below the sustainability target of 0.50g
Cleaner than an estimated 86% of websites analyzed. This page meets the Web Sustainability Guidelines target.
Info::
Estimated 14th percentile
Compared to: top 10% = 0.20g, target = 0.50g, median = 0.60g per page view.
Top 10%
Target
Median website

0.25g

14th percentile

Cleaner than 86% of websites

✓ Below the Web Sustainability Guidelines target

vs Median 59% cleaner ✓
vs Target 51% 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: Tessellate OS

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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