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

2 PASS 2 REVIEW 3 FIX

CO2 Per Page Load

Action

1.33g CO2 per view

FIX

1.33g CO2 per view

1.33g CO2 per page view

This page transfers 4.7 MB, producing an estimated 1.33g of CO2 per visit using the Sustainable Web Design model (v4). Breakdown: data center 0.25g, network 0.23g, end-user device 0.85g.

Got: 1.33g CO2 Expected: < 0.50g (sustainability target)

At 10,000 monthly views: 159.3 kg CO2/year

With 10,000 page views per month, this page would generate approximately 159.3 kg of CO2 annually — equivalent to charging 19909 smartphones.

1.33g

Carbon Footprint per page view

✗ Above sustainability target (0.50g)

Cleaner than 30% of websites

Sustainable Web Design model v4 · Page size: 4.7 MB

Your site

1.33g

Top 10%

0.20g

Target

0.50g

Median website

0.60g

Energy Breakdown

Data center

0.25g

Network

0.23g

End-user device

0.85g

At 10,000 monthly views: Monthly: 13.3 kg · Annual: 159.3 kg · ≈ 19909 smartphone charges

Green Hosting

Action

Not green

FIX

Not green

No confirmed renewable energy commitment detected

Consider providers like Cloudflare, Google Cloud, or Vercel that match 100% of their energy use with renewables.

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 HostingNot Green Hosted

Hosting Next.js✗CDN Not identified✗

Based on known provider commitments. Verify at thegreenwebfoundation.org

Carbon Budget

Action

70th percentile

FIX

70th percentile

1.33g CO2 — above the median website (0.60g)

Heavier than an estimated 30% of websites. Reducing page weight, optimizing images, and removing unused JavaScript would lower the carbon footprint. See the Performance tab.

Estimated 70th percentile

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

Top 10%

Target

Median website

1.33g

70th percentile

Cleaner than 30% of websites

✗ Above the median website

vs Median 121% more

vs Target 165% more

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.

Green Hosting

Action

Whether the site is served from green-energy infrastructure

REVIEW

Green Hosting

No green hosting detected

A+

Repeat Visit Weight

99% cached

PASS

99% cached

99% reduction on repeat visits

Returning visitors download only 33 KB (vs 4799 KB first visit). 108 of 109 resources are served from browser cache, saving 1.32g CO2 per repeat visit.

Repeat visit: 0.01g CO2 (first visit: 1.33g)

First visit

4799 KB

Repeat visit

33 KB

99% reduction on repeat visits

Saving 1.32g CO2 per returning visitor

108 resources served from cache · 1 resources re-downloaded

A+

Transfer Efficiency

96% efficient

PASS

96% efficient

Transfer efficiency: 96%

Only 209 KB of potential savings identified. Your page is well-optimized for size.

Total waste: 209 KB (4% of page weight)

Unused JS 209 KB

0.06g unnecessary CO2 per visit

Actual transfer 4799 KB

Theoretical minimum 4590 KB

Potential savings 209 KB (0.06g CO2)

See Deep Analysis sections above for specific optimizations.

Image Optimization

6 images, 0 KB total, 0 KB wasted

INFO

Image Optimization Audit

Total Images

Total Size

0 KB

Oversized

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