What is the average 401k fee?

Could you please clarify what the average 401k fee typically entails? I'm curious to know if there's a standard rate that investors can expect to pay, or if it varies significantly depending on factors such as the size of the account, the investment options offered, and the service provider. Additionally, I'd like to understand if there are any hidden fees that investors should be aware of when it comes to managing their 401k accounts. Could you provide a concise overview of the typical fees associated with a 401k plan?