Sustainability

· 7 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

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

0.29g CO2 per view

PASS

0.29g CO2 per view

0.29g CO2 per page view

This page transfers 1.2 MB, producing an estimated 0.29g of CO2 per visit using the Sustainable Web Design model (v4). Breakdown: data center 0.01g, network 0.06g, end-user device 0.23g.

Got: 0.29g CO2 Expected: < 0.50g (sustainability target)

At 10,000 monthly views: 35.3 kg CO2/year

With 10,000 page views per month, this page would generate approximately 35.3 kg of CO2 annually — equivalent to charging 4418 smartphones.

Green hosting reduces data center emissions

0.29g

Carbon Footprint per page view

✓ Below sustainability target (0.50g)

Cleaner than 81% of websites

Sustainable Web Design model v4 · Page size: 1.2 MB

Your site

0.29g

Top 10%

0.20g

Target

0.50g

Median website

0.60g

Energy Breakdown

Data center

0.01g

Network

0.06g

End-user device

0.23g

At 10,000 monthly views: Monthly: 2.9 kg · Annual: 35.3 kg · ≈ 4418 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

100% cached

PASS

100% cached

100% reduction on repeat visits

Returning visitors download only 4 KB (vs 1274 KB first visit). 40 of 41 resources are served from browser cache, saving 0.29g CO2 per repeat visit.

Repeat visit: 0.00g CO2 (first visit: 0.29g)

First visit

1274 KB

Repeat visit

4 KB

100% reduction on repeat visits

Saving 0.29g CO2 per returning visitor

40 resources served from cache · 1 resources re-downloaded

Carbon Budget

19th percentile

PASS

19th percentile

0.29g CO2 — below the sustainability target of 0.50g

Cleaner than an estimated 81% of websites analyzed. This page meets the Web Sustainability Guidelines target.

Estimated 19th percentile

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

Top 10%

Target

Median website

0.29g

19th percentile

Cleaner than 81% of websites

✓ Below the Web Sustainability Guidelines target

vs Median 51% cleaner ✓

vs Target 41% cleaner ✓

A+

Transfer Efficiency

91% efficient

PASS

91% efficient

Transfer efficiency: 91%

Only 117 KB of potential savings identified. Your page is well-optimized for size.

Total waste: 117 KB (9% of page weight)

Unused JS 117 KB

0.03g unnecessary CO2 per visit

Actual transfer 1274 KB

Theoretical minimum 1156 KB

Potential savings 117 KB (0.03g 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.