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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
72
GRADE
C
FIX
2
REVIEW
0
PASS
4
INFO
0
Device:
Mobile Desktop
Checks
6
4 PASS 2 FIX
F
CO2 Per Page Load
Action
1.70g CO2 per view
FIX
1.70g CO2 per view
Warning::
1.70g CO2 per page view
This page transfers 7.2 MB, producing an estimated 1.70g of CO2 per visit using the Sustainable Web Design model (v4). Breakdown: data center 0.04g, network 0.35g, end-user device 1.30g.
Got: 1.70g CO2 Expected: < 0.50g (sustainability target)
Info::
At 10,000 monthly views: 203.5 kg CO2/year
With 10,000 page views per month, this page would generate approximately 203.5 kg of CO2 annually — equivalent to charging 25436 smartphones.
Info::
Green hosting reduces data center emissions

1.70g

Carbon Footprint per page view

✗ Above sustainability target (0.50g)

Cleaner than 19% of websites

Sustainable Web Design model v4 · Page size: 7.2 MB

Your site
1.70g
Top 10%
0.20g
Target
0.50g
Median website
0.60g

Energy Breakdown

Data center
0.04g
Network
0.35g
End-user device
1.30g
At 10,000 monthly views: Monthly: 17.0 kg · Annual: 203.5 kg · ≈ 25436 smartphone charges
F
Carbon Budget
Action
81th percentile
FIX
81th percentile
Warning::
1.70g CO2 — above the median website (0.60g)
Heavier than an estimated 19% of websites. Reducing page weight, optimizing images, and removing unused JavaScript would lower the carbon footprint. See the Performance tab.
Info::
Estimated 81th percentile
Compared to: top 10% = 0.20g, target = 0.50g, median = 0.60g per page view.
Top 10%
Target
Median website

1.70g

81st percentile

Cleaner than 19% of websites

✗ Above the median website

vs Median 183% more
vs Target 239% 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
98% cached
PASS
98% cached
Info::
98% reduction on repeat visits
Returning visitors download only 134 KB (vs 7336 KB first visit). 78 of 79 resources are served from browser cache, saving 1.66g CO2 per repeat visit.
Info::
Repeat visit: 0.03g CO2 (first visit: 1.70g)
First visit
7336 KB
Repeat visit
134 KB

98% reduction on repeat visits

Saving 1.66g CO2 per returning visitor

78 resources served from cache · 1 resources re-downloaded

A+
Transfer Efficiency
99% efficient
PASS
99% efficient
Info::
Transfer efficiency: 99%
Only 76 KB of potential savings identified. Your page is well-optimized for size.
99% efficient

Total waste: 76 KB (1% of page weight)

Unused JS 76 KB

0.02g unnecessary CO2 per visit

Actual transfer 7336 KB
Theoretical minimum 7260 KB
Potential savings 76 KB (0.02g 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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