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

5 PASS 2 REVIEW

Transfer Efficiency

77% efficient

REVIEW

77% efficient

Transfer efficiency: 77%

An estimated 265 KB (23%) could be eliminated: 0 KB via better compression, 0 KB via modern image formats, 265 KB of unused JavaScript. This wasted data produces 0.06g of unnecessary CO2 per page view.

Total waste: 265 KB (23% of page weight)

Unused JS 265 KB

0.06g unnecessary CO2 per visit

Actual transfer 1176 KB

Theoretical minimum 910 KB

Potential savings 265 KB (0.06g CO2)

See Deep Analysis sections above for specific optimizations.

Web Font Weight Variants

No detectable Google Fonts weights

REVIEW

No detectable Google Fonts weights

The analyzer detects font weights via Google Fonts URL parameters (~70% of font-using sites). Self-hosted fonts and non-Google CDN fonts aren't visible to URL-based detection. If you self-host fonts, manually audit how many @font-face weights you ship -- 2-3 weights per family is typically enough; 5+ is usually unused payload.

CO2 Per Page Load

0.27g CO2 per view

PASS

0.27g CO2 per view

0.27g CO2 per page view

This page transfers 1.1 MB, producing an estimated 0.27g of CO2 per visit using the Sustainable Web Design model (v4). Breakdown: data center 0.01g, network 0.06g, end-user device 0.21g.

Got: 0.27g CO2 Expected: < 0.50g (sustainability target)

At 10,000 monthly views: 32.6 kg CO2/year

With 10,000 page views per month, this page would generate approximately 32.6 kg of CO2 annually — equivalent to charging 4078 smartphones.

Green hosting reduces data center emissions

0.27g

Carbon Footprint per page view

✓ Below sustainability target (0.50g)

Cleaner than 83% of websites

Sustainable Web Design model v4 · Page size: 1.1 MB

Your site

0.27g

Top 10%

0.20g

Target

0.50g

Median website

0.60g

Energy Breakdown

Data center

0.01g

Network

0.06g

End-user device

0.21g

At 10,000 monthly views: Monthly: 2.7 kg · Annual: 32.6 kg · ≈ 4078 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

97% cached

PASS

97% cached

97% reduction on repeat visits

Returning visitors download only 36 KB (vs 1176 KB first visit). 65 of 66 resources are served from browser cache, saving 0.26g CO2 per repeat visit.

Repeat visit: 0.01g CO2 (first visit: 0.27g)

First visit

1176 KB

Repeat visit

36 KB

97% reduction on repeat visits

Saving 0.26g CO2 per returning visitor

65 resources served from cache · 1 resources re-downloaded

Carbon Budget

17th percentile

PASS

17th percentile

0.27g CO2 — below the sustainability target of 0.50g

Cleaner than an estimated 83% of websites analyzed. This page meets the Web Sustainability Guidelines target.

Estimated 17th percentile

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

Top 10%

Target

Median website

0.27g

17th percentile

Cleaner than 83% of websites

✓ Below the Web Sustainability Guidelines target

vs Median 55% cleaner ✓

vs Target 46% cleaner ✓

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

21 images, 483 KB total, 0 KB wasted

INFO

Image Optimization Audit

Total Images

Total Size

483 KB

1 missing lazy loading

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