90 Day Prescription Refill Calculator



Calculating the refill date for a 90-day prescription can be a cumbersome task, especially when considering the varying number of days in each month. To simplify this process, we’ve created a user-friendly 90 Day Prescription Refill Calculator using HTML and JavaScript. This article will guide you through its usage, explain the underlying formula, provide examples, address frequently asked questions, and conclude with the importance of this tool.

How to Use

The 90 Day Prescription Refill Calculator is straightforward to use. Simply input the start date of your prescription and click the “Calculate” button. The tool will display the accurate refill date, considering the specific number of days in each month.


The formula used in the calculator is precise and accounts for the number of days in each month, ensuring accurate results. It takes into consideration the start date and calculates the end date based on a 90-day period.


Let’s say your prescription starts on January 1, 2024. By using the calculator, you can determine the refill date by clicking the “Calculate” button. The tool will then provide you with the accurate date for your 90-day prescription refill.


Q1: How accurate is the calculation?
A1: The calculator uses a precise formula that accounts for the varying days in each month, providing accurate results.

Q2: Can I use the calculator for prescriptions starting on any date?
A2: Yes, the calculator is designed to work with prescriptions starting on any date, ensuring flexibility for users.

Q3: Does the calculator consider leap years?
A3: Yes, the formula takes leap years into account, ensuring accuracy in calculations.


The 90 Day Prescription Refill Calculator simplifies the process of determining the refill date for your prescriptions. Its accurate formula and user-friendly interface make it a valuable tool for individuals managing their medications with 90-day supplies.

Leave a Comment