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https://www.stripe.dev

Sustainability

· 6 checks — CO2 emissions, green hosting, repeat-visit weight, carbon budget, and transfer efficiency rolled into one auditable list.
SCORE
89
GRADE
B
FIX
0
REVIEW
2
PASS
4
INFO
0
Device:
Mobile Desktop
Checks
6
4 PASS 2 REVIEW
C
Transfer Efficiency
Action
64% efficient
REVIEW
64% efficient
Warning::
Transfer efficiency: 64%
An estimated 227 KB (36%) could be eliminated: 0 KB via better compression, 0 KB via modern image formats, 227 KB of unused JavaScript. This wasted data produces 0.05g of unnecessary CO2 per page view.
64% efficient

Total waste: 227 KB (36% of page weight)

Unused JS 227 KB

0.05g unnecessary CO2 per visit

Actual transfer 638 KB
Theoretical minimum 410 KB
Potential savings 227 KB (0.05g CO2)

See Deep Analysis sections above for specific optimizations.

C
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
Info::
0.15g CO2 per page view
This page transfers 0.6 MB, producing an estimated 0.15g of CO2 per visit using the Sustainable Web Design model (v4). Breakdown: data center 0.00g, network 0.03g, end-user device 0.11g.
Got: 0.15g CO2 Expected: < 0.50g (sustainability target)
Info::
At 10,000 monthly views: 17.7 kg CO2/year
With 10,000 page views per month, this page would generate approximately 17.7 kg of CO2 annually — equivalent to charging 2212 smartphones.
Info::
Green hosting reduces data center emissions

0.15g

Carbon Footprint per page view

✓ Below sustainability target (0.50g)

Cleaner than 90% of websites

Sustainable Web Design model v4 · Page size: 0.6 MB

Your site
0.15g
Top 10%
0.20g
Target
0.50g
Median website
0.60g

Energy Breakdown

Data center
0.00g
Network
0.03g
End-user device
0.11g
At 10,000 monthly views: Monthly: 1.5 kg · Annual: 17.7 kg · ≈ 2212 smartphone charges
A
Green Hosting
Green (cdn)
PASS
Green (cdn)
Info::
Vercel CDN uses renewable energy
Since most traffic is served through the CDN, the majority of data transfer energy is renewable.
Info::
Vercel: Hosted on AWS/Google Cloud with renewable energy commitments
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.js✗CDN Vercel✓

Vercel: Hosted on AWS/Google Cloud with renewable energy commitments

Based on known provider commitments. Verify at thegreenwebfoundation.org

A+
Repeat Visit Weight
98% cached
PASS
98% cached
Info::
98% reduction on repeat visits
Returning visitors download only 14 KB (vs 638 KB first visit). 47 of 48 resources are served from browser cache, saving 0.14g CO2 per repeat visit.
Info::
Repeat visit: 0.00g CO2 (first visit: 0.15g)
First visit
638 KB
Repeat visit
14 KB

98% reduction on repeat visits

Saving 0.14g CO2 per returning visitor

47 resources served from cache · 1 resources re-downloaded

A+
Carbon Budget
10th percentile
PASS
10th percentile
Info::
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.
Info::
Estimated 10th percentile
Compared to: top 10% = 0.20g, target = 0.50g, median = 0.60g per page view.
Top 10%
Target
Median website

0.15g

10th percentile

Cleaner than 90% of websites

✓ Below the Web Sustainability Guidelines target

vs Median 75% cleaner ✓
vs Target 70% cleaner ✓
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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