Ladies Period Predictor Calculator

How This Works

This is a simple user interface for the menstrual cycle predictor calculator. The form consists of three input fields:

A input element with an id of "last-period" is used to collect the date of the user's last menstrual period.

A input element with an id of "cycle-length" is used to collect the average length of the user's menstrual cycle. It also have min and max attributes that limit the number of days between 21-35. A Input element with an id of "luteal-phase" is used to collect the average length of the user's luteal phase, also have min and max attributes that limit the number of days between 12-16. A button is provided to trigger the JavaScript function that calculates the next period.

This function starts by getting the values of the form inputs, it converts the value entered in the date input field to a JavaScript Date object. It then uses the setDate() method to add the number of days in the menstrual cycle (cycleLength) minus the number of days in the luteal phase (lutealPhase) to the date of the last period. The result is the estimated date of the next period.

The final step of the function is to display the result on the web page using the innerHTML property of the

element with an id of "result". The toLocaleDateString() method is used to format the date as a string that is appropriate for the user's local.

It's worth noting that this example does not have any client-side validation, so it is possible for the user to enter invalid data (for example, a cycle length less than 21 days or greater than 35 days). In a real-world application, you will likely want to add validation to ensure that the user enters valid data.