Around 300-500 words is a common response, but we’d say there’s no right or wrong answer here. They should be snappy, concise, and easily digestible, and provide all the necessary information for a customer to make an informed purchase decision.
It also depends on your brand style and tone of voice. If you opt for bullet points rather than full sentences, your copy is likely to be on the shorter side. If you choose to add FAQs, your product descriptions will be on the longer end.