Period Calculator & Online Period Tracker

Free period calculator to predict your next period, track your menstrual cycle, and identify your fertile window. Our web-based period tracker is completely private - no account needed to calculate your period dates.

Free Period Calculator & Menstrual Cycle Calculator

Our period calculator helps you predict your next period date, ovulation day, and fertile window. This online period tracker uses your cycle data to create a personalized menstrual cycle calendar. Simply answer three questions below to calculate your period dates and get your monthly cycle chart.

When did your
last period start?

How many days does
your period usually last?

What's your
usual cycle length?

Your Period Calculator Results - Monthly Cycle Chart

Your personalized period calculator results showing your predicted periods, fertile window, and ovulation days for the next 12 months. This period tracker web calendar helps you plan ahead with accurate period predictions.

Current Month

Period Days

Ovulation

Fertile Window

Pre-Period

Note: This period tracker is only an estimation. Your unique menstrual cycle may vary from these results.

What Users Say About Our Period Tracker

"I've been looking for a simple period tracker that doesn't require an account or share my data. The Cylo Care web tracker is perfect - it's straightforward and gives me exactly what I need."

Priya V

"The ability to save as PDF and print my tracker is so useful! I can easily share this with my doctor during appointments. Clean design and very user-friendly."

Jessica R.

"I appreciate how this tracker shows not just period days but also fertility windows and ovulation. It's been accurate for my cycle and I love the visual calendar format."

Aanya

"After trying various period trackers, I finally found one that doesn't share my data! The calendar view is easy to understand and the predictions have been spot on for me."

Emily Johnson

"I love that I can just visit the website without installing an app. The tracker is so simple to use, and the calendar visualization makes it easy to plan ahead."

Deepika M.

"I was worried about privacy with most period apps. This web tracker is perfect because I know my data isn't being collected or sold. Thank you for creating this!"

Neha Gupta

"Super helpful for planning ahead! I can see when my period will fall months in advance, which has been great for planning trips and important events."

Sarah Miller

"The interface is clean and intuitive. I love that I can see my fertile window and ovulation days clearly marked. It's helped me be more aware of my cycle phases."

Maya H

"Great for basic tracking. I've been using it for 6 months and it's been pretty accurate for my cycle. The PDF feature is a nice bonus for keeping records."

Christina B.

"I switched to this tracker after being concerned about privacy with other period apps. So glad I did - it's simple, effective, and I control my own data!"

Divya Joshi

"I've been looking for a simple period tracker that doesn't require an account or share my data. The Cylo Care web tracker is perfect - it's straightforward and gives me exactly what I need."

Priya V

"The ability to save as PDF and print my tracker is so useful! I can easily share this with my doctor during appointments. Clean design and very user-friendly."

Jessica R.

"I appreciate how this tracker shows not just period days but also fertility windows and ovulation. It's been accurate for my cycle and I love the visual calendar format."

Aanya

"Fantastic web tool! I've been using it for three months and it's helped me understand my cycle patterns so much better. The predictions are surprisingly accurate."

Ashley T.

Frequently Asked Questions

How accurate is the web period tracker?

The Cylo Care web period tracker provides estimations based on the information you enter about your cycle. For most women with regular cycles, it offers reasonably accurate predictions. However, many factors can affect your menstrual cycle, including stress, health conditions, and lifestyle changes. For the most accurate tracking, we recommend downloading our app for more comprehensive features.

Is my data private when I use the web tracker?

What do the different colored days mean on the calendar?

Can I save my period tracking information?

How does the period calculator work?

Our period calculator uses your last period date, typical period length, and cycle length to predict your next period dates. The calculator algorithm estimates ovulation day (typically 14 days before your next period) and fertile window (5 days before ovulation plus 1 day after). This online period calculator provides accurate predictions for most women with regular cycles.

Is this period calculator online free to use?

What's the difference between period tracker web and mobile apps?

Our period tracker web version works directly in your browser without downloading anything. It's perfect for quick period calculations and one-time use. The web period tracker offers the same calculation accuracy as mobile apps but with complete privacy since no data is stored on servers. Mobile apps may offer additional features like notifications and automatic data saving.

Want More Than Just a Period Calculator?

While our web period calculator provides accurate period predictions, download the Cylo Care app for comprehensive period tracking with advanced features, private symptom tracking, and personalized cycle insights—all with complete privacy.

Download Cylo Care App