A good ROAS (Return on Ad Spend) on Amazon is generally considered between 3:1 and 4:1. It means that you are generating $3 or $4 in revenue for every $1 you spend on PPC advertising. However, the ideal ROAS can vary significantly based on industry, product type, and specific business goals. For example, highly competitive industries may consider 2:1 or even lower as a good ROAS figure, while less competitive industries might aim for ROAS of 5:1 or higher.