According to relevant information, under normal circumstances, the calculation method of provident fund loan based on the balance of provident fund account is: the amount of provident fund loan is equal to the balance of lender's provident fund account multiplied by 20. Therefore, if the balance of the provident fund account is 1 1,000 yuan, multiplied by 20, the loanable amount is 20,000 yuan. For detailed information, it is best to consult the local official website for first-hand authoritative information.