There are two types of IPOs, namely, fixed price issue and book building issue.
In a fixed price issue, the company after evaluation sets a fixed price for the offering, and investors are required to pay the fixed price to apply for the IPO.
In a book building issue, the company after evaluation discloses a price band and investors may select a price between the price band. The price of the allotment is decided based on the highest bids on a particular price.