Predict when your premenstrual symptoms might occur based on your unique cycle.
Next Expected Period:
PMS Symptom Window Starts:
PMS Symptom Window Ends:
Estimated Ovulation Day:
Understanding Your PMS Cycle
Premenstrual Syndrome (PMS) refers to a wide range of physical and emotional symptoms that many people experience in the days leading up to their menstrual period. While every individual's experience is different, these symptoms typically occur during the luteal phase of the menstrual cycle, which is the time between ovulation and the start of your next period.
How This Calculator Works
The PMS Cycle Calculator uses standard biological timelines to estimate your upcoming cycle phases. It assumes a standard luteal phase of approximately 14 days. Here is the math behind the predictions:
Next Period: Calculated by adding your average cycle length (e.g., 28 days) to the start date of your last period.
Ovulation: Generally occurs 14 days before your next period begins.
PMS Window: Symptoms usually begin about 10 to 14 days before your period starts and typically subside once your period begins.
Common PMS Symptoms to Track
By using a PMS calculator, you can prepare for common symptoms such as:
Physical: Bloating, breast tenderness, headaches, fatigue, and changes in appetite.
Emotional: Irritability, mood swings, anxiety, and difficulty concentrating.
Sleep: Changes in sleep patterns or insomnia.
Example Calculation
If your last period started on June 1st and you have a 28-day cycle:
Your next period is predicted for June 29th.
Your PMS symptoms might start appearing around June 15th (14 days before June 29th).
Ovulation would likely occur around June 15th as well.
Why Track Your PMS Cycle?
Tracking your cycle is about more than just knowing when your period will arrive. It helps you identify patterns in your mental health and physical wellbeing. If you notice severe symptoms that interfere with your daily life, this data is incredibly valuable to share with your healthcare provider to discuss conditions like PMDD (Premenstrual Dysphoric Disorder).
function calculatePMSCycle() {
var lastDateVal = document.getElementById("lastPeriodDate").value;
var cycleLengthVal = document.getElementById("cycleLength").value;
if (!lastDateVal) {
alert("Please select the date of your last period.");
return;
}
var cycleLength = parseInt(cycleLengthVal);
if (isNaN(cycleLength) || cycleLength 100) {
alert("Please enter a valid cycle length (typical cycles are between 21 and 35 days).");
return;
}
var lastDate = new Date(lastDateVal);
// Calculate Next Period
var nextPeriodDate = new Date(lastDate);
nextPeriodDate.setDate(lastDate.getDate() + cycleLength);
// Calculate PMS Start (typically 14 days before next period)
var pmsStartDate = new Date(nextPeriodDate);
pmsStartDate.setDate(nextPeriodDate.getDate() – 14);
// Calculate Ovulation (typically 14 days before next period)
var ovulationDate = new Date(nextPeriodDate);
ovulationDate.setDate(nextPeriodDate.getDate() – 14);
// Date Format Options
var options = { weekday: 'long', year: 'numeric', month: 'long', day: 'numeric' };
// Output results
document.getElementById("nextPeriodOutput").innerHTML = nextPeriodDate.toLocaleDateString(undefined, options);
document.getElementById("pmsStartOutput").innerHTML = pmsStartDate.toLocaleDateString(undefined, options);
document.getElementById("pmsEndOutput").innerHTML = nextPeriodDate.toLocaleDateString(undefined, options) + " (Symptoms usually end as period starts)";
document.getElementById("ovulationOutput").innerHTML = ovulationDate.toLocaleDateString(undefined, options);
// Show result container
document.getElementById("pmsResults").style.display = "block";
// Scroll to results
document.getElementById("pmsResults").scrollIntoView({ behavior: 'smooth', block: 'nearest' });
}