** “Clue is knowledge about your cycle, about science, about yourself.” — Apple **

** Best Fertility Tracking Apps of 2019. — Healthline **

** The top free period tracker app. — Obstetrics & Gynecology, a publication of the American College of Obstetricians & Gynecologists (ACOG). **

Clue is the #1 period tracker app that uses science and smart technology to help you demystify your menstrual cycle. Join millions of users who trust Clue for spot-on period predictions, a good indication for when to expect cramps and PMS, and accurate ovulation and fertility tracking. The Clue app is scientific and straightforward: no flowers, pink, or butterflies—just the facts about your cycle.

Clue arms you with knowledge about your body that you can use every day. Over 30+ tracking categories help you identify cyclical patterns in your health and everything from menstruation to birth control, mood, and sex habits can all be logged and customised based on your preferences. Plus, set reminders so you never get surprised by your period or cramps again.

Period & Cycle Tracking:
+ Track your period, flow heaviness, and the menstrual products you use
+ Receive accurate predictions and calendar reminders before your next period, PMS, and ovulation
+ Use the calendar to view past periods, PMS, and fertility data, as well as upcoming predictions for your next three cycles
+ Log your birth control type & set pill reminders
+ Integration with Healthkit, including Health App, Touch ID, and Today Extension

Ovulation & Fertility Tracking:
+ See predictions of your fertile days & get a better indication of when you’re ovulating
+ Log your basal temperature (BBT)—perfect if you’re trying to conceive

Chart your Cycle Data:
+ Easily view your period data & stats such as average cycle length, period length, & recurring symptoms
+ Define what is normal or not for your body by observing normalities & irregularities in your cycle
+ Bring Clue to your next doctor’s appointment & have your cycle data on-hand

Clue goes beyond just adding a period to a calendar. Here’s how we are different:

+ We are the only period tracker that partners with world-class research institutions & universities to provide you with the most accurate cycle predictions.
+ We don’t sell your data. Your privacy is and always has been our priority
+ We are inclusive & use gender-neutral language so anyone with a cycle can use our app
+ We are here to educate & empower. We encourage you to learn not only when your periods occur, but why and how menstruation and reproduction work

Upgrade to Clue Plus, where a subscription gets you:
+ An in-depth monthly email report of your personal cycle stats
+ Exclusive health content delivered in-app
+ Discounts & giveaways of our favorite period products

After you choose one of our plans & confirm your purchase, the payment will be charged to your credit card through your iTunes Account.

Renewal: Once purchased, subscriptions will automatically renew unless auto-renew is turned off at least 24-hours before the end of the current period.

If you decide to renew your subscription, your account will be charged the same amount you paid for your initial subscription within 24-hours prior to the end of the current period. At any time you can manage your subscription & turn off auto-renewal by going to the Account Settings on your device after the purchase.

Note: Clue Period & Cycle Tracker should *not* be used as a contraceptive.

Send your feedback, questions, & suggestions to
Twitter: @clue
IG: @clueapp

Terms of Service:
Privacy Policy:

What’s New

Version 9.1

Traveling for the holidays? Traveling across time zones can have an impact on your hormones – the further you go, the more likely you are to be affected.

The menstrual cycle is influenced by travel because of its hormonal relationship to your circadian rhythms (your body’s daily cycles). When jumping across time zones, it takes time for your hormones to get back into balance. If you plan on traveling a lot during the holiday season, then you might notice some changes to your period, such as a late start – but don’t worry! Once you get back into a normal routine again, then your menstrual cycles will return to your body’s average length within a cycle or two. #NowYouKnow

From everyone here at Clue, happy holidays!

(We managed to squeeze in some final 2019 performance enhancements and bug fixes. If you run into any trouble, let us know at

Ratings and Reviews

4.7 out of 5
22.8K Ratings

22.8K Ratings

Laurin4475 ,

Such a great period tracker

I started using Clue when I had to go off the pill, and was trying to predict when my period would arrive. It made it much easier to see what was happening, and helped me understand my body better. It was an invaluable resource for tracking my fertility when we were trying to conceive, and I missed being able to use it when I was pregnant!
I would recommend this app above all other period trackers.
If there was one improvement that I wish you could make, it would be to implement pregnancy into the app. Even just to be able to tell the app you’re pregnant, so it doesn’t expect you to input data about period for a number of months would be great. Although it is good that when I’ve opened it up after 11 months that it understands that that time wasn’t one long cycle. It would be great to be able to input that you’re breastfeeding, and be able to use information such as birth date etc, so the app knows to expect various different symptoms (and probably not a regular cycle) for a time afterwards.

Shadow6Meg ,

Good but for me it desperately needs a journal

This app is really simple to use and has a great visual circle to show where abouts you are in your cycle which is nice.

It also has a nice information helper as well with pictures you can click on to track how you’re feeling, if you felt like eating or if you slept a lot etc. on one hand I like this because it helps keeps things uniform and easy to track and on the other hand I can’t stand it because it keeps things too uniform and there is no where to add extra details if something else is effecting your health. For example I might be sick this week or I might be more tired then usual due to work picking up or being more active then normal. I think it would be really nice if there was a way to write down extra details like that. Perhaps you could make it so people originally write the journal entry in the regular symptoms detail entering place then it shows up in the calendar with all the rest. Perhaps have the journal entries primarily show up in the zoomed in one column, daily calendar page. Perhaps have the first sentence or a few sentences of the journal entry be visible under the symptoms to keep it compact but with the ability to click on them to view/create larger journal entries.

Overall I really like some aspects of the app but I feel like the inability for the user to add detailed information could really hurt it. It’s something that has made me consider changing apps quite a few times.

lowcals ,

The best tracking app I’ve found

This app is incredible compared to basic calendars and calculator apps that I have used in the past. It’s motivated me to get into a routine and pay more attention to my health. The reason I didn’t give it 5 stars is because I would like there to be a few more options in each category (or the ability to add options per category). For emotions you can only select; happy, sad, sensitive or PMS. I want to be able to add things like; flat, irritable, excited, hopeful, moody etc. I’m rarely just happy or sad. Same goes with energy levels; an option for a neutral level of energy would be great. I have endometriosis so this app is fantastic because I’ve always been interested to gauge the different phases of my cycle in more detail. Providing some extra information and symptoms for those with endometriosis or PCOS would be wonderful too (for now I have added some customised symptoms). I’d also love LOVE if there was notes about the phases of the moon as these generally have massive correlations with our cycles and it’s super interesting to gauge and learn more about. Great job with this app. I’m looking forward to using it more and hopefully seeing some addditional functions in the future! :) thank you!!


BioWink GmbH
137.7 MB

Requires iOS 11.0 and watchOS 4.0 or later. Compatible with iPhone, iPad and iPod touch.


English, Danish, French, German, Hindi, Italian, Japanese, Korean, Polish, Portuguese, Russian, Simplified Chinese, Spanish, Traditional Chinese, Turkish

Age Rating
Infrequent/Mild Mature/Suggestive Themes
Infrequent/Mild Medical/Treatment Information
In-App Purchases
  1. 12 Months $13.99
  2. 1 Month $1.49
  3. 1 Month $9.99


  • Family Sharing

    Up to six family members will be able to use this app with Family Sharing enabled.

You May Also Like