Current source backbone
Google Search Central documentation
Google AdSense Help and Publisher Policies
PayPal Business Fees
Stripe Pricing
Etsy Fees and Payments Policy
Amazon Seller Pricing
Shopify official company and commerce pages
SellerGauge
Sources
We use official or primary-source documentation wherever we can for rates, platform fees, and tax references. Here is what we rely on most.
Source handling
When a page uses a simplified assumption for speed, we label it and link to the closest official source available so you can check it yourself.