When using a Pag-IBIG loan calculator, ensure you have the following details: the loan amount you're considering, the interest rate, and the loan term. Additionally, gather information on your monthly contributions and any other fees associated with the loan. This will help you estimate your monthly repayments accurately. It’s also wise to check with Pag-IBIG or a financial advisor for specific details related to your situation, as they can provide tailored advice and the most current information.