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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
94
GRADE
A
FIX
0
REVIEW
0
PASS
6
INFO
0
Device:
Mobile Desktop
Checks
6
6 PASS
A
CO2 Per Page Load
0.36g CO2 per view
PASS
0.36g CO2 per view
Info::
0.36g CO2 per page view
This page transfers 1.5 MB, producing an estimated 0.36g of CO2 per visit using the Sustainable Web Design model (v4). Breakdown: data center 0.01g, network 0.07g, end-user device 0.28g.
Got: 0.36g CO2 Expected: < 0.50g (sustainability target)
Info::
At 10,000 monthly views: 43.2 kg CO2/year
With 10,000 page views per month, this page would generate approximately 43.2 kg of CO2 annually — equivalent to charging 5405 smartphones.
Info::
Green hosting reduces data center emissions

0.36g

Carbon Footprint per page view

✓ Below sustainability target (0.50g)

Cleaner than 74% of websites

Sustainable Web Design model v4 · Page size: 1.5 MB

Your site
0.36g
Top 10%
0.20g
Target
0.50g
Median website
0.60g

Energy Breakdown

Data center
0.01g
Network
0.07g
End-user device
0.28g
At 10,000 monthly views: Monthly: 3.6 kg · Annual: 43.2 kg · ≈ 5405 smartphone charges
A+
Green Hosting
Green (both)
PASS
Green (both)
Info::
Both hosting and CDN use renewable energy
Got: Hosting: Platform.sh, CDN: Cloudflare
Info::
Platform.sh: Verified by the Green Web Foundation
Info::
Cloudflare: 100% renewable energy for global network since 2019
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 Platform.sh✓CDN Cloudflare✓

Platform.sh: Verified by the Green Web Foundation

Cloudflare: 100% renewable energy for global network since 2019

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 19 KB (vs 1559 KB first visit). 59 of 60 resources are served from browser cache, saving 0.36g CO2 per repeat visit.
Info::
Repeat visit: 0.00g CO2 (first visit: 0.36g)
First visit
1559 KB
Repeat visit
19 KB

99% reduction on repeat visits

Saving 0.36g CO2 per returning visitor

59 resources served from cache · 1 resources re-downloaded

A
Carbon Budget
26th percentile
PASS
26th percentile
Info::
0.36g CO2 — below the sustainability target of 0.50g
Cleaner than an estimated 74% of websites analyzed. This page meets the Web Sustainability Guidelines target.
Info::
Estimated 26th percentile
Compared to: top 10% = 0.20g, target = 0.50g, median = 0.60g per page view.
Top 10%
Target
Median website

0.36g

26th percentile

Cleaner than 74% of websites

✓ Below the Web Sustainability Guidelines target

vs Median 40% cleaner ✓
vs Target 28% cleaner ✓
A+
Transfer Efficiency
91% efficient
PASS
91% efficient
Info::
Transfer efficiency: 91%
Only 146 KB of potential savings identified. Your page is well-optimized for size.
91% efficient

Total waste: 146 KB (9% of page weight)

Unused JS 146 KB

0.03g unnecessary CO2 per visit

Actual transfer 1559 KB
Theoretical minimum 1412 KB
Potential savings 146 KB (0.03g CO2)

See Deep Analysis sections above for specific optimizations.

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

Green Hosting

This site is hosted on green energy infrastructure

Provider: Cloudflare

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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