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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
66
GRADE
D
FIX
2
REVIEW
0
PASS
4
INFO
0
Device:
Mobile Desktop
Checks
6
4 PASS 2 FIX
F
CO2 Per Page Load
Action
3.34g CO2 per view
FIX
3.34g CO2 per view
Critical::
3.34g CO2 per page view
This page transfers 14.1 MB, producing an estimated 3.34g of CO2 per visit using the Sustainable Web Design model (v4). Breakdown: data center 0.08g, network 0.69g, end-user device 2.57g.
Got: 3.34g CO2 Expected: < 0.50g (sustainability target)
Info::
At 10,000 monthly views: 400.9 kg CO2/year
With 10,000 page views per month, this page would generate approximately 400.9 kg of CO2 annually — equivalent to charging 50108 smartphones.
Info::
Green hosting reduces data center emissions

3.34g

Carbon Footprint per page view

✗ Above sustainability target (0.50g)

Cleaner than 5% of websites

Sustainable Web Design model v4 · Page size: 14.1 MB

Your site
3.34g
Top 10%
0.20g
Target
0.50g
Median website
0.60g

Energy Breakdown

Data center
0.08g
Network
0.69g
End-user device
2.57g
At 10,000 monthly views: Monthly: 33.4 kg · Annual: 400.9 kg · ≈ 50108 smartphone charges
F
Carbon Budget
Action
95th percentile
FIX
95th percentile
Warning::
3.34g CO2 — above the median website (0.60g)
Heavier than an estimated 5% of websites. Reducing page weight, optimizing images, and removing unused JavaScript would lower the carbon footprint. See the Performance tab.
Info::
Estimated 95th percentile
Compared to: top 10% = 0.20g, target = 0.50g, median = 0.60g per page view.
Top 10%
Target
Median website

3.34g

95th percentile

Cleaner than 5% of websites

✗ Above the median website

vs Median 457% more
vs Target 568% more
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
99% cached
PASS
99% cached
Info::
99% reduction on repeat visits
Returning visitors download only 76 KB (vs 14452 KB first visit). 172 of 174 resources are served from browser cache, saving 3.32g CO2 per repeat visit.
Info::
Repeat visit: 0.02g CO2 (first visit: 3.34g)
First visit
14452 KB
Repeat visit
76 KB

99% reduction on repeat visits

Saving 3.32g CO2 per returning visitor

172 resources served from cache · 2 resources re-downloaded

A+
Transfer Efficiency
99% efficient
PASS
99% efficient
Info::
Transfer efficiency: 99%
Only 204 KB of potential savings identified. Your page is well-optimized for size.
99% efficient

Total waste: 204 KB (1% of page weight)

Unused JS 204 KB

0.05g unnecessary CO2 per visit

Actual transfer 14452 KB
Theoretical minimum 14247 KB
Potential savings 204 KB (0.05g 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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