It is important to choose a niche that you are passionate and knowledgeable about to create high-quality content that resonates with your audience. You can start by researching popular niches with high demand and low competition.

Some niches that tend to perform well in affiliate marketing include health and wellness, personal finance, beauty and skincare, technology, and online education. These niches have a broad audience and offer numerous products and services to promote, making it easier to find profitable affiliate programs.

However, keep in mind that competition can be fierce in popular niches, so finding a unique angle or sub-niche can help you stand out. Additionally, conducting thorough keyword research and SEO optimization can increase your visibility and traffic.

Ultimately, the best niche for an affiliate website depends on your interests, expertise, and the needs and interests of your target audience.