The formula
We start from your traffic: visitors × the share who open the chat = conversations, then × messages per chat = total messages. Each message costs the words going in (your instructions, the visitor's text, a bit of the earlier chat and any help-doc snippets) plus the words the bot writes back. Add up every message and add the cost of chats handed to a person.
Questions
How much does an AI chatbot cost per month?
Anything from a few dollars for a quiet FAQ bot to a few hundred for a busy support bot. It comes down to how many chats you get, how long they run, which model you pick, and whether the bot searches your help docs.
Does searching my help docs cost more?
A little. Each snippet the bot pulls in adds to the message, and there's a tiny charge to search. It's usually still cheap - just pull in only what you need.
Which model should my chatbot use?
A small, fast model handles most support and FAQ questions well. Save the pricey models for tricky reasoning or areas where a wrong answer is costly.