It is natural for those who are aware of the concept of SEO's and know that they exist to think if there are any rankings for such firms. They would also wonder how the ranking is done, what aspects it is based on and how the ranking separates one company from another. 

Basically, they would want to know the criteria for judging an SEO agency. When comparing SEO agencies, we should look at its functions and the outcomes they are able to obtain for their clients keeping in mind the rest of the market. You can also browse to find a SEO company. 

For this to be done well, the customer needs should be analyzed well. An SEO agency can easily generalize solutions for clients. The era today is of customization. If a client wants a solution customized to his own website, he deserves to have it.

Another factor to look at is the clientele of an SEO agency. If two firms are in existence for the same time period, it is not wrong to assume that the one with a larger client base will be better than the other. However, it is equally important that the variety of clients serviced should also differ.