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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
87
GRADE
B
FIX
0
REVIEW
2
PASS
4
INFO
0
Device:
Mobile Desktop
Checks
6
4 PASS 2 REVIEW
B
Carbon Budget
33th percentile
REVIEW
33th percentile
Info::
0.43g CO2 — below the sustainability target of 0.50g
Cleaner than an estimated 67% of websites analyzed. This page meets the Web Sustainability Guidelines target.
Info::
Estimated 33th percentile
Compared to: top 10% = 0.20g, target = 0.50g, median = 0.60g per page view.
Top 10%
Target
Median website

0.43g

33rd percentile

Cleaner than 67% of websites

✓ Below the Web Sustainability Guidelines target

vs Median 28% cleaner ✓
vs Target 14% cleaner ✓
B
Transfer Efficiency
79% efficient
REVIEW
79% efficient
Info::
Transfer efficiency: 79%
An estimated 398 KB (21%) could be eliminated: 0 KB via better compression, 0 KB via modern image formats, 398 KB of unused JavaScript. This wasted data produces 0.09g of unnecessary CO2 per page view.
79% efficient

Total waste: 398 KB (21% of page weight)

Unused JS 398 KB

0.09g unnecessary CO2 per visit

Actual transfer 1862 KB
Theoretical minimum 1463 KB
Potential savings 398 KB (0.09g CO2)

See Deep Analysis sections above for specific optimizations.

A
CO2 Per Page Load
0.43g CO2 per view
PASS
0.43g CO2 per view
Info::
0.43g CO2 per page view
This page transfers 1.8 MB, producing an estimated 0.43g of CO2 per visit using the Sustainable Web Design model (v4). Breakdown: data center 0.01g, network 0.09g, end-user device 0.33g.
Got: 0.43g CO2 Expected: < 0.50g (sustainability target)
Info::
At 10,000 monthly views: 51.7 kg CO2/year
With 10,000 page views per month, this page would generate approximately 51.7 kg of CO2 annually — equivalent to charging 6457 smartphones.
Info::
Green hosting reduces data center emissions

0.43g

Carbon Footprint per page view

✓ Below sustainability target (0.50g)

Cleaner than 67% of websites

Sustainable Web Design model v4 · Page size: 1.8 MB

Your site
0.43g
Top 10%
0.20g
Target
0.50g
Median website
0.60g

Energy Breakdown

Data center
0.01g
Network
0.09g
End-user device
0.33g
At 10,000 monthly views: Monthly: 4.3 kg · Annual: 51.7 kg · ≈ 6457 smartphone charges
A+
Green Hosting
Green (both)
PASS
Green (both)
Info::
Both hosting and CDN use renewable energy
Got: Hosting: Next.js, CDN: Cloudflare
Info::
Next.js: 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 Next.js✓CDN Cloudflare✓

Next.js: 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
92% cached
PASS
92% cached
Info::
92% reduction on repeat visits
Returning visitors download only 153 KB (vs 1862 KB first visit). 84 of 85 resources are served from browser cache, saving 0.40g CO2 per repeat visit.
Info::
Repeat visit: 0.04g CO2 (first visit: 0.43g)
First visit
1862 KB
Repeat visit
153 KB

92% reduction on repeat visits

Saving 0.40g CO2 per returning visitor

84 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: 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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