Amazon's monthly sales volume is a relatively large number, because Amazon is one of the largest e-commerce companies in the world, and sales are affected by many factors, including product variety, brand awareness, market competition, etc.

According to Amazon's financial report, its global net sales reached 280.2 billion US dollars in 2019, equivalent to an average monthly sales volume of 23.4 billion US dollars. This figure is in line with the scale of Amazon as a huge company, but the specific normal sales volume still needs to be judged according to the specific circumstances of the company.

For small and medium-sized enterprises or individual sellers, monthly sales may be lower. Depending on the product type and market competition, sales of millions or even lower per month can also be considered a normal range.

In short, normal Amazon monthly sales volume will vary in different situations, and it needs to be comprehensively judged based on factors such as company size, product type, and market competition.