Sustainability

· 8 checks — CO2 emissions, green hosting, repeat-visit weight, carbon budget, and transfer efficiency rolled into one auditable list.

SCORE

GRADE

FIX

REVIEW

PASS

INFO

Device:

Mobile Desktop

Checks

6 PASS 1 REVIEW

Transfer Efficiency

78% efficient

REVIEW

78% efficient

Transfer efficiency: 78%

An estimated 242 KB (22%) could be eliminated: 0 KB via better compression, 0 KB via modern image formats, 242 KB of unused JavaScript. This wasted data produces 0.06g of unnecessary CO2 per page view.

Total waste: 242 KB (22% of page weight)

Unused JS 242 KB

0.06g unnecessary CO2 per visit

Actual transfer 1105 KB

Theoretical minimum 862 KB

Potential savings 242 KB (0.06g CO2)

See Deep Analysis sections above for specific optimizations.

CO2 Per Page Load

0.26g CO2 per view

PASS

0.26g CO2 per view

0.26g CO2 per page view

This page transfers 1.1 MB, producing an estimated 0.26g of CO2 per visit using the Sustainable Web Design model (v4). Breakdown: data center 0.01g, network 0.05g, end-user device 0.20g.

Got: 0.26g CO2 Expected: < 0.50g (sustainability target)

At 10,000 monthly views: 30.7 kg CO2/year

With 10,000 page views per month, this page would generate approximately 30.7 kg of CO2 annually — equivalent to charging 3832 smartphones.

Green hosting reduces data center emissions

0.26g

Carbon Footprint per page view

✓ Below sustainability target (0.50g)

Cleaner than 85% of websites

Sustainable Web Design model v4 · Page size: 1.1 MB

Your site

0.26g

Top 10%

0.20g

Target

0.50g

Median website

0.60g

Energy Breakdown

Data center

0.01g

Network

0.05g

End-user device

0.20g

At 10,000 monthly views: Monthly: 2.6 kg · Annual: 30.7 kg · ≈ 3832 smartphone charges

A+

Green Hosting

Green (both)

PASS

Green (both)

Both hosting and CDN use renewable energy

Got: Hosting: Next.js, CDN: Cloudflare

Next.js: Verified by the Green Web Foundation

Cloudflare: 100% renewable energy for global network since 2019

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

89% cached

PASS

89% cached

89% reduction on repeat visits

Returning visitors download only 119 KB (vs 1105 KB first visit). 78 of 85 resources are served from browser cache, saving 0.23g CO2 per repeat visit.

Repeat visit: 0.03g CO2 (first visit: 0.26g)

First visit

1105 KB

Repeat visit

119 KB

89% reduction on repeat visits

Saving 0.23g CO2 per returning visitor

78 resources served from cache · 7 resources re-downloaded

Carbon Budget

15th percentile

PASS

15th percentile

0.26g CO2 — below the sustainability target of 0.50g

Cleaner than an estimated 85% of websites analyzed. This page meets the Web Sustainability Guidelines target.

Estimated 15th percentile

Compared to: top 10% = 0.20g, target = 0.50g, median = 0.60g per page view.

Top 10%

Target

Median website

0.26g

15th percentile

Cleaner than 85% of websites

✓ Below the Web Sustainability Guidelines target

vs Median 57% cleaner ✓

vs Target 49% cleaner ✓

A+

Web Font Weight Variants

3 font weights loaded across 3 famil(y/ies) -- reasonable

PASS

3 font weights loaded across 3 famil(y/ies) -- reasonable

3 font weight(s) loaded across 3 famil(y/ies)

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

Image Optimization

9 images, 72 KB total, 59 KB wasted

INFO

Image Optimization Audit

Total Images

Total Size

72 KB

Oversized

Wasted

59 KB

9 missing dimensions

All checks on this page are automated. Results are estimates - run targeted manual reviews when the score affects a release decision.