Period & Menstrual Cycle Calculator
Track Your Cycle, Predict Ovulation & Forecast Next Periods
Understanding Your Menstrual Cycle
A typical menstrual cycle lasts between 21-35 days. The first day of your period is considered Day 1 of your cycle. Ovulation usually occurs about 14 days before your next period begins.
Fertility Window
Your fertile window includes the 5 days before ovulation and the day of ovulation itself. The highest chance of conception occurs in the 2-3 days before ovulation.
Disclaimer
Important: This calculator provides estimates based on averages. Your actual cycle may vary. Not to be used for contraceptive purposes. Consult your healthcare provider for medical advice.
🩸 How to Use the Period Calculator Tool
Step 1: Select the First Day of Your Last Menstrual Period
Start by choosing the exact date when your last period began. This critical step allows the calculator to accurately estimate the timing of your next menstrual cycle and ovulation window.
Step 2: Enter Your Average Cycle Length in Days
Input the typical length of your menstrual cycle — usually between 21 and 35 days. This information helps the tool predict the timing of your next period and fertile days with greater accuracy.
Step 3: Get Your Predicted Period and Ovulation Calendar
Once the data is entered, the calculator will generate a full visual calendar showing your upcoming periods, ovulation day, and fertile window. This allows you to plan ahead for travel, workouts, fertility tracking, or health monitoring.
Step 4: Adjust for Irregular Cycles (If Needed)
If your cycles aren’t regular, you can input previous cycle data to fine-tune the accuracy. The tool adapts to your patterns and provides predictions that are more in line with your unique cycle.
Step 5: Download, Share, or Track Your Cycle History
After calculation, you can save your menstrual and ovulation chart as a PDF or image. Use it to track your health, discuss with your doctor, or sync with wellness apps for better cycle management.
🩸 Track Your Last Period
Enter the first day of your last period to begin tracking your menstrual cycle. This helps predict when your next period is likely to start, and sets a reliable base for the entire calculation.
📆 Know Your Cycle Length
Provide your average cycle length (typically 21–35 days). Our tool uses this to calculate future periods, ovulation days, and fertile windows accurately — ideal for managing menstrual health.
🌸 Estimate Your Next Period
The calculator shows your next expected period date, helping you stay prepared with period products and avoid surprises. It’s perfect for event planning, travel, or managing your fitness routine.
🧬 Identify Ovulation & Fertile Days
Based on your input, the tool highlights your fertile window and ovulation day, useful for those trying to conceive or practicing natural birth control. Timing is key for fertility and planning!
📱 Works on All Devices
Our period calculator is fully mobile-friendly, working seamlessly on phones, tablets, and desktops. Access your menstrual cycle predictions anytime, anywhere, with ease and convenience.
💾 Download & Share Results
After calculating, you can download or save your personalized period calendar to track your cycle easily. Great for sharing with your doctor, planning pregnancy, or tracking symptoms over time.