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 4 REVIEW 1 FIX

Green Hosting

Action

Unknown

FIX

Unknown

Hosting provider could not be identified

Without knowing the provider, we cannot determine their energy sourcing. Check with your hosting provider about their renewable energy commitments.

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 HostingUnable to Determine

Hosting Not identified✗CDN Not identified✗

Based on known provider commitments. Verify at thegreenwebfoundation.org

CO2 Per Page Load

0.54g CO2 per view

REVIEW

0.54g CO2 per view

0.54g CO2 per page view

This page transfers 1.9 MB, producing an estimated 0.54g of CO2 per visit using the Sustainable Web Design model (v4). Breakdown: data center 0.10g, network 0.09g, end-user device 0.35g.

Got: 0.54g CO2 Expected: < 0.50g (sustainability target)

At 10,000 monthly views: 65.1 kg CO2/year

With 10,000 page views per month, this page would generate approximately 65.1 kg of CO2 annually — equivalent to charging 8134 smartphones.

0.54g

Carbon Footprint per page view

✗ Above sustainability target (0.50g)

Cleaner than 56% of websites

Sustainable Web Design model v4 · Page size: 1.9 MB

Your site

0.54g

Top 10%

0.20g

Target

0.50g

Median website

0.60g

Energy Breakdown

Data center

0.10g

Network

0.09g

End-user device

0.35g

At 10,000 monthly views: Monthly: 5.4 kg · Annual: 65.1 kg · ≈ 8134 smartphone charges

Carbon Budget

44th percentile

REVIEW

44th percentile

0.54g CO2 — below the median website (0.60g)

Better than an estimated 56% of websites, but above the sustainability target of 0.50g. Reducing page weight would help reach the target.

Estimated 44th percentile

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

Top 10%

Target

Median website

0.54g

44th percentile

Cleaner than 56% of websites

✗ Above the median website

vs Median 10% cleaner ✓

vs Target 8% 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 19 KB (vs 1960 KB first visit). 68 of 69 resources are served from browser cache, saving 0.54g CO2 per repeat visit.

Repeat visit: 0.01g CO2 (first visit: 0.54g)

First visit

1960 KB

Repeat visit

19 KB

99% reduction on repeat visits

Saving 0.54g CO2 per returning visitor

68 resources served from cache · 1 resources re-downloaded

A+

Transfer Efficiency

94% efficient

PASS

94% efficient

Transfer efficiency: 94%

Only 126 KB of potential savings identified. Your page is well-optimized for size.

Total waste: 126 KB (6% of page weight)

Unused JS 126 KB

0.03g unnecessary CO2 per visit

Actual transfer 1960 KB

Theoretical minimum 1834 KB

Potential savings 126 KB (0.03g CO2)

See Deep Analysis sections above for specific optimizations.

Image Optimization

29 images, 49 KB total, 0 KB wasted

INFO

Image Optimization Audit

Total Images

Total Size

49 KB

2 missing alt text 14 missing dimensions 11 missing lazy loading

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