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

3 PASS 3 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

Repeat Visit Weight

80% cached

REVIEW

80% cached

80% reduction on repeat visits

Returning visitors download only 109 KB (vs 535 KB first visit). 27 of 28 resources are served from browser cache, saving 0.12g CO2 per repeat visit.

Repeat visit: 0.03g CO2 (first visit: 0.15g)

First visit

535 KB

Repeat visit

109 KB

80% reduction on repeat visits

Saving 0.12g CO2 per returning visitor

27 resources served from cache · 1 resources re-downloaded

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+

CO2 Per Page Load

0.15g CO2 per view

PASS

0.15g CO2 per view

0.15g CO2 per page view

This page transfers 0.5 MB, producing an estimated 0.15g of CO2 per visit using the Sustainable Web Design model (v4). Breakdown: data center 0.03g, network 0.03g, end-user device 0.09g.

Got: 0.15g CO2 Expected: < 0.50g (sustainability target)

At 10,000 monthly views: 17.8 kg CO2/year

With 10,000 page views per month, this page would generate approximately 17.8 kg of CO2 annually — equivalent to charging 2219 smartphones.

0.15g

Carbon Footprint per page view

✓ Below sustainability target (0.50g)

Cleaner than 90% of websites

Sustainable Web Design model v4 · Page size: 0.5 MB

Your site

0.15g

Top 10%

0.20g

Target

0.50g

Median website

0.60g

Energy Breakdown

Data center

0.03g

Network

0.03g

End-user device

0.09g

At 10,000 monthly views: Monthly: 1.5 kg · Annual: 17.8 kg · ≈ 2219 smartphone charges

A+

Carbon Budget

10th percentile

PASS

10th percentile

0.15g CO2 — below the sustainability target of 0.50g

Cleaner than an estimated 90% of websites analyzed. This page meets the Web Sustainability Guidelines target.

Estimated 10th percentile

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

Top 10%

Target

Median website

0.15g

10th percentile

Cleaner than 90% of websites

✓ Below the Web Sustainability Guidelines target

vs Median 75% cleaner ✓

vs Target 70% cleaner ✓

A+

Transfer Efficiency

100% efficient

PASS

100% efficient

Transfer efficiency: 100%

Only 0 KB of potential savings identified. Your page is well-optimized for size.

Actual transfer 535 KB

Theoretical minimum 535 KB

See Deep Analysis sections above for specific optimizations.

Image Optimization

110 images, 13 KB total, 6 KB wasted

INFO

Image Optimization Audit

Total Images

110

Total Size

13 KB

Oversized

Wasted

6 KB

13 missing alt text 20 missing dimensions 34 missing lazy loading

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