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https://rewordsai.app

Sustainability

· 8 checks — CO2 emissions, green hosting, repeat-visit weight, carbon budget, and transfer efficiency rolled into one auditable list.
SCORE
91
GRADE
A
FIX
0
REVIEW
2
PASS
5
INFO
1
Checks
8
5 PASS 2 REVIEW
B
Transfer Efficiency
78% efficient
REVIEW
78% efficient
Info::
Transfer efficiency: 78%
An estimated 193 KB (22%) could be eliminated: 0 KB via better compression, 0 KB via modern image formats, 193 KB of unused JavaScript. This wasted data produces 0.04g of unnecessary CO2 per page view.
78% efficient

Total waste: 193 KB (22% of page weight)

Unused JS 193 KB

0.04g unnecessary CO2 per visit

Actual transfer 882 KB
Theoretical minimum 688 KB
Potential savings 193 KB (0.04g CO2)

See Deep Analysis sections above for specific optimizations.

B
Web Font Weight Variants
No detectable Google Fonts weights
REVIEW
No detectable Google Fonts weights
Info::
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.
A
CO2 Per Page Load
0.20g CO2 per view
PASS
0.20g CO2 per view
Info::
0.20g CO2 per page view
This page transfers 0.9 MB, producing an estimated 0.20g of CO2 per visit using the Sustainable Web Design model (v4). Breakdown: data center 0.01g, network 0.04g, end-user device 0.16g.
Got: 0.20g CO2 Expected: < 0.50g (sustainability target)
Info::
At 10,000 monthly views: 24.5 kg CO2/year
With 10,000 page views per month, this page would generate approximately 24.5 kg of CO2 annually — equivalent to charging 3059 smartphones.
Info::
Green hosting reduces data center emissions

0.20g

Carbon Footprint per page view

Below sustainability target (0.50g)

Cleaner than 90% of websites

Sustainable Web Design model v4 · Page size: 0.9 MB

Your site
0.20g
Top 10%
0.20g
Target
0.50g
Median website
0.60g

Energy Breakdown

Data center
0.01g
Network
0.04g
End-user device
0.16g
At 10,000 monthly views: Monthly: 2.0 kg · Annual: 24.5 kg · ≈ 3059 smartphone charges
A+
Green Hosting
Green (both)
PASS
Green (both)
Info::
Both hosting and CDN use renewable energy
Got: Hosting: Next.js, CDN: Cloudflare
Info::
Next.js: Verified by the Green Web Foundation
Info::
Cloudflare: 100% renewable energy for global network since 2019
Info::
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.jsCDN 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
95% cached
PASS
95% cached
Info::
95% reduction on repeat visits
Returning visitors download only 43 KB (vs 882 KB first visit). 104 of 105 resources are served from browser cache, saving 0.19g CO2 per repeat visit.
Info::
Repeat visit: 0.01g CO2 (first visit: 0.20g)
First visit
882 KB
Repeat visit
43 KB

95% reduction on repeat visits

Saving 0.19g CO2 per returning visitor

104 resources served from cache · 1 resources re-downloaded

A+
Carbon Budget
10th percentile
PASS
10th percentile
Info::
0.20g CO2 — below the sustainability target of 0.50g
Cleaner than an estimated 90% of websites analyzed. This page meets the Web Sustainability Guidelines target.
Info::
Estimated 10th percentile
Compared to: top 10% = 0.20g, target = 0.50g, median = 0.60g per page view.
Top 10%
Target
Median website

0.20g

10th percentile

Cleaner than 90% of websites

Below the Web Sustainability Guidelines target

vs Median 66% cleaner ✓
vs Target 59% 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
12 images, 50 KB total, 0 KB wasted
INFO

Image Optimization Audit

Total Images

12

Total Size

50 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.

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