Widely used publicly available tools are DeBot and Botometer (formerly BotOrNot). But they have been criticized for inaccuracy. Many people would say there are no reliable publicly available tools for bot detection
Identifying bots is one of the most prevalent industry practices, and many tools are available for this. One such tool is FollowersAnalysis.
There are various tools that can help you in the identification of fake followers. One such excellent tool is FollowersAnalysis. They specialize in studying Twitter followers and their usage patterns which allows them to separate the needles from the haystack.
Getting a detailed account analysis is the most effective solution available today to maintain the authenticity of a Twitter account.
Although Twitter has taken steps to curb this issue but considering the size and reach of Twitter, it is easier said than done.