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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::
OpenGSE uses renewable energy
Info::
OpenGSE: 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 OpenGSE✓CDN Not identified✗

OpenGSE: Verified by the Green Web Foundation

Based on known provider commitments. Verify at thegreenwebfoundation.org

B
Transfer Efficiency
90% efficient
REVIEW
90% efficient
Info::
Transfer efficiency: 90%
An estimated 139 KB (10%) could be eliminated: 0 KB via better compression, 0 KB via modern image formats, 139 KB of unused JavaScript. This wasted data produces 0.03g of unnecessary CO2 per page view.
90% efficient

Total waste: 139 KB (10% of page weight)

Unused JS 139 KB

0.03g unnecessary CO2 per visit

Actual transfer 1346 KB
Theoretical minimum 1207 KB
Potential savings 139 KB (0.03g CO2)

See Deep Analysis sections above for specific optimizations.

A
CO2 Per Page Load
0.31g CO2 per view
PASS
0.31g CO2 per view
Info::
0.31g CO2 per page view
This page transfers 1.3 MB, producing an estimated 0.31g of CO2 per visit using the Sustainable Web Design model (v4). Breakdown: data center 0.01g, network 0.06g, end-user device 0.24g.
Got: 0.31g CO2 Expected: < 0.50g (sustainability target)
Info::
At 10,000 monthly views: 37.4 kg CO2/year
With 10,000 page views per month, this page would generate approximately 37.4 kg of CO2 annually — equivalent to charging 4669 smartphones.
Info::
Green hosting reduces data center emissions

0.31g

Carbon Footprint per page view

✓ Below sustainability target (0.50g)

Cleaner than 79% of websites

Sustainable Web Design model v4 · Page size: 1.3 MB

Your site
0.31g
Top 10%
0.20g
Target
0.50g
Median website
0.60g

Energy Breakdown

Data center
0.01g
Network
0.06g
End-user device
0.24g
At 10,000 monthly views: Monthly: 3.1 kg · Annual: 37.4 kg · ≈ 4669 smartphone charges
A+
Repeat Visit Weight
96% cached
PASS
96% cached
Info::
96% reduction on repeat visits
Returning visitors download only 59 KB (vs 1346 KB first visit). 51 of 52 resources are served from browser cache, saving 0.30g CO2 per repeat visit.
Info::
Repeat visit: 0.01g CO2 (first visit: 0.31g)
First visit
1346 KB
Repeat visit
59 KB

96% reduction on repeat visits

Saving 0.30g CO2 per returning visitor

51 resources served from cache · 1 resources re-downloaded

A
Carbon Budget
21th percentile
PASS
21th percentile
Info::
0.31g CO2 — below the sustainability target of 0.50g
Cleaner than an estimated 79% of websites analyzed. This page meets the Web Sustainability Guidelines target.
Info::
Estimated 21th percentile
Compared to: top 10% = 0.20g, target = 0.50g, median = 0.60g per page view.
Top 10%
Target
Median website

0.31g

21st percentile

Cleaner than 79% of websites

✓ Below the Web Sustainability Guidelines target

vs Median 48% cleaner ✓
vs Target 38% 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: Google Cloud

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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