Account Questions

How do I set up a PeakDay Account?

First, download the PeakDay app.  If you do not have a CycleProGo account, create a username and password.  Select your subscription plan and begin your free trial period.  After this, begin charting!

You can also watch the video: "How do I get started with PeakDay?".


How do I change or reset my password?

Go to Settings > General Settings > and you can change your password.  If you do not know your current password, please logout and click on “Forgot Username or Password?” and follow the instructions sent to your email.

You can also watch the video: "How do I reset my password".


Can I change my subscription type?

Yes!  Go to Settings > Subscription Settings > Select Your Plan > Subscribe and make payment if applicable.  Please make sure to also cancel your current monthly or annual subscription you changed from in your phone’s recurring subscriptions.


How do I find my PeakDay app username? 

In PeakDay, click on the Settings button and your username is listed at the top under the word “Settings”.


Is there a refund policy?

There is an initial free trial period. Per our Terms and Conditions, we do not offer refunds for PeakDay subscriptions. You may cancel your subscription to PeakDay at any time. PeakDay does not provide refunds or the right to return for a purchased subscription.


How to check for your Peak Day expiration date.

You can check your expiration date in PeakDay! Once you have Peak Day open, tap on “Settings” in the bottom right and then choose “Subscription Settings”.  On this “Subscription Settings” page, you will be able to see when your current subscription ends.  You can also check the Apple and Google app stores first to see if there is a subscription purchased and the date.


Why is my data not showing up on my chart right away?

Your data is safely secured in our sever.  This makes it so your important charting information is accessible anywhere, from multiple and most devices.  If there is ever a loss of connection, your device may need to resync to view your data.  To do so, tap on the “Refresh” button.  This will reestablish the connection and have you up and running again!


Where can I find information about the Privacy Policy for PeakDay?



Where can I find information about data security and safety for PeakDay?



Why does the rule I use change back to the STM rule each cycle?

If changing a chart rule from STM to anything else, such as the temperature only rule for example, please note that once a new chart is started, the default STM rule will reapply.


How can I view a current or prior cycle day without swiping through symptoms?

To have a more comprehensive and quicker view of a cycle day, instead of clicking into a day as if to input data, try clicking the “See More” button on the home page of PeakDay.  This will allow you to quickly view prior input data including personal notes!


Some of my symptom inputs are missing.  What should I do?

If you are missing vital symptom inputs such as temperature or mucus or maybe you just want to have more information for a specific day, please do the following...

  1. Once in PeakDay, tap on the current day or any prior to get to the “Record Symptoms” page.
  2. From here, there are symptoms boxes along the top. Tap on the last box to the right that has a “+” and is labeled “Additional”.
  3. In “Additional”, you can check-mark any symptoms available you want to track and even add personal notes for the day.
  4. Tap save after selecting the desired inputs.

All chosen inputs will show up every day from here on out.

Charting Questions

How to chart bleeding?

Heavy is heavy or normal flow.  Light indicates partial or lighter flow.  Spotting is very light flow or small amounts.


In Phase 1, what does “undetermined” mean?

"Undetermined” means that without mucus data the app is unable to determine what phase you are in.  Please add more mucus data or setup an appointment with a coach for a deeper look into your chart.


What is basal body temperature?

The basal body temperature is the temperature of the human body at rest or upon awakening, unaffected by food, drink, or activity.  A woman's basal body temperature rises slightly after ovulation in response to progesterone, so recording the basal body temperature throughout the menstrual cycle provides important information.


What kind of thermometer should I use?

Use a basal body thermometer. STM rule is based on research done with the basal body temperature taken to the tenths place. The PeakDay app will round temperatures up or down to the 10th place, so you can input temperatures to the 100ths if you prefer (i.e., 97.42 = 97.4, 97.48 = 97.5).

You may purchase a basal body temperature thermometer: Digital Basal Body Thermometer.


How do I take my temperature?

With a digital basal thermometer, you can take your temperature in a minute.  To maintain accuracy, it is a good idea to stay in bed while you take it.  Some models beep differently when taking the temperature than when the reading is complete.  Check your model's directions for details.


When should I take my temperature?

Take your temperature at the same time every day (or at least within one-half hour of your waking time).  Make a note on your chart if you take your temperature earlier or later than this acceptable interval.  Note: Getting up briefly during the night (i.e., to care for an infant) will not affect your normal waking temperature if you get a minimum of six hours of sleep, in total, and have rested again for at least one hour before taking your temperature.


When taking my temperature, should I record to the hundredth’s degree?  Is it more accurate?

STM rule is based on research done with the basal body temperature taken to the tenths place. Even though a thermometer may give a temperature to the hundredths place, that may make it more precise but not necessarily more accurate.  Check your thermometer for its certified accuracy.  It may be certified accurate to the tenths place but will read to the hundredths.


When should I check “Ignore Temperature”?

You should take your basal body temperature at the same time each day (or at least within one-half hour of your waking time).  When you do not take your temperature within this time frame, you cannot be assured that it accurately reflects your basal body temperature on that day.  Additionally, there are other situations, such as sickness, lack of sleep, travel, or other types of stress that could cause a higher or lower reading than would normally be expected on a given day of a cycle.  On other occasions, the temperature may be taken at the specified time, but when recorded on the chart, it appears to be out of the range of the surrounding temperatures. When a temperature is clearly out of the range of the surrounding temperatures, it is an abnormal temperature.


What is an insufficient mucus pattern?

An insufficient mucus pattern is when a number of more fertile mucus days are needed to find peak day.  Please set up an appointment with a coach to improve your mucus pattern.


Why is my chart not showing other phases or is only white or green?

Your chart may be missing data.  Please set up an appointment with a coach for a deeper look into your chart.


Why is the number input pad not going away when I am recording my temperature on my Android?

On an Android phone/device, when typing in a temperature please choose "done" or the check mark to close the number input pad.  The app may not record the temperature if you do not.


How do I check and record cervix signs? 

Although the cervix observation is optional, it can be a helpful sign that provides a woman with a more complete picture of her fertility, can reduce the number of days of abstinence, and can help during times of transition, such as postpartum (after eight weeks) or perimenopause.

Please go to to take a class or to to find a coach who can teach you how to check and record your cervix.


I have a longer chart.  Why does it always show on day one when I go to view?

Now that PeakDay enables charting as long as needed, viewing a longer chart can take a moment to get used to.  To scroll or zoom on a chart, two fingers are always required.  Please note that every chart, regardless of length, will default to the first day.  Charts may also be viewed in a web browser to increase size and viewability.


I entered a symptom incorrectly, can I edit my data?

To edit data for another day, click on the date in the calendar and then click the yellow “edit” button.  Edit any data by moving to the screen you want, or by touching the data input you want to edit at the top.  Edit your data and then click the green “save” button in the upper right of the screen.


How do I customize what items are available to choose each day?

Go to Settings > Fertility Intention & Event Settings.  Here you can choose what items display by toggling on the symptoms you would like to record and see displayed on your chart.


What do the different colors on my home calendar signify?

The three colors signify the different phases of the fertility cycle.  Phase 1 is yellow and is non-fertile; phase 2 is green and is a fertile time; phase 3 is purple and is an infertile time.


Why does a day have two colors?

Any day that is split between green and purple indicates that phase 3, the infertile phase, will start on the evening of that day.  The morning is fertile (green) and the evening is infertile (purple).


Why don’t I see different colors on my calendar?  Everything is white.

The day may show the phase as Undetermined and uncolored if you have not added data for the day.  Add Symptoms using the “+” in the bottom menu or edit the day. (see below).

You need a premium subscription for the app to give you the fertile and infertile phases.  You can change your subscription at any time by going to Settings > Subscription Settings > Select Your Plan and subscribe.


How do I tell what phase I am in?

The app will indicate which phase you are in based on the color on the calendar.  For today, please see the info on the bottom half of the screen.  It will have the date and list the phase.


How do I share my chart?

In the app go to “Get Help” and choose “Share Your Chart”.  You can share your chart with anyone via text or email by clicking on “Share” under “Share with anyone by sending a link”.

Postpartum (Nursing and Formula) or Perimenopause Questions

I am Postpartum, Nursing or Perimenopause.  What should I know for PeakDay?

Please go into the Settings > Fertility Intention & Event Settings > Turn "On" the BIP counter.  PeakDay will still apply the BIP rules, but the count will not show on your chart unless you turn this on.


When should I use Postpartum charting? 

You should choose that a new cycle is postpartum charting when you first start recording symptoms after a pregnancy.


Where do I go to chart after having my baby/Postpartum?

Start charting when your lochia ends, or you observe mucus or bleeding (refer to the postpartum class guidelines). On the Bleeding input page, click the box to indicate “This day should start a new cycle.” Another box with “Regular Cycle Charting” pops up.  Use the arrow on the right to see more options.  Then choose the Postpartum Charting that fits you.  This cycle will then use those postpartum rules. Find the date of your baby’s birth on the calendar.  Edit this day. On the Bleeding input, click the box to indicate “This day should start a new cycle.” Another box with “Regular Cycle Charting” pops up.  Use the arrow on the right to see more options.  Then choose the Postpartum Charting that fits you.  This cycle will then use the postpartum rules.


I am postpartum.  What should I set as my first cycle day?

  • If you are postpartum formula feeding, use your baby’s birthday as first day of cycle.
  • If you are postpartum nursing, use first day of bleeding or mucus to start cycle.


When should I use Perimenopause charting?

Only use the perimenopause charting when you are confirmed to be in this transition as defined be CCL’s Transitions Student Guide and/or Perimenopause class.  If you are still not sure if you are in perimenopause, then ask a certified teacher or coach at


Where do I go to chart during Perimenopause?

You can choose the perimenopause charting on the first day of a new cycle.  When you click the box to indicate “This day should start a new cycle” another box with “Regular Cycle Charting” pops up.  Use the arrow on the right to see more options.  Then choose Perimenopause Charting.  This cycle will then use the perimenopause rules.


Note:  Genital contact between a man and woman can lead to pregnancy. The PeakDay app is a tool to assist you in your decision-making and help you become the authority about your own fertility.

Phase I Rules

If trying to postpone pregnancy, coitus should only be on evenings of non-consecutive days in Phase I to allow for detection of mucus.

Day 5/6 Rule

Assume infertility on Cycle Days 1-5.

For women with cycles 26 days or longer in the last 12 cycles, assume infertility on Cycle Days 1-6.

Conditions for use:

  • This rule assumes the absence of mucus.

Doering Rule

Subtract seven from the earliest first day of temperature rise in the last 12 cycles. Mark that cycle day as the last day that you can assume Phase I infertility.

Conditions for use:

  • This rule assumes the absence of mucus.
  • This rule requires six cycles of temperature history.

Last Dry Day Rule

The end of Phase I is the last day without mucus sensations or characteristics.

Conditions for use:

  • This rule requires six cycles of experience.
  • Woman should have at least six days of mucus from its onset through Peak Day.

Phase III Rules

Sympto-Thermal Rule

Phase III begins on the evening of:

  1. The third day of drying-up after Peak Day, combined with
  2. three normal post-peak temperatures above the LTL, and
  3. the third temperature at or above the HTL or the cervix closed and hard for three days

If the above conditions are not met, then Phase III begins after waiting an additional post-peak day for another temperature above the LTL.

Temperature-Only Rule

Phase III begins on the evening of the fourth day of normal temperatures above the LTL. The last three temperatures must be on consecutive days, and at or above the HTL.

Mucus-Only Rule

Phase III begins on the evening of the fourth day of drying up or thickening of the mucus after Peak Day.

Post-Hormonal Rule

For the first cycle after stopping the hormones, Phase III begins on the evening of:

  1. The fourth day of drying-up after Peak Day, combined with
  2. Four normal post-peak temperatures above the LTL.

If discontinuing injectable hormones, discuss with your Teaching Couple and see the Reference Guide section of The Art of Natural Family Planning® Student Guide..

Postpartum and Premenopause

Note: If you are postpartum or in premenopause for more than 10 months or so, you need to create a new chart by checking this box for "this day should start a new chart". Breaking up charts makes them easier to navigate. CycleProGo will not analyze a chart lasting longer than 1 year. For these reasons, you should break up your charts. (This will not start a new cycle, just a new chart.)

Mucus Patch Rule

Phase I infertility returns on the evening of the fourth day of dry, nothing after the last day of the mucus patch or non-menstrual bleed.

Conditions for use:

  1. Postpartum Breastfeeding or Premenopause
  2. No thermal shift

BIP Rule

Phase I infertility begins when a Basic Infertile Pattern is established and returns on the evening of the fourth day of return to the BIP.

Conditions for use:

  1. Postpartum Breastfeeding or Premenopause
  2. No thermal shift
Additional Considerations:
  1. You should record a Mucus Description when postpartum or in premenopause. This is a brief description of your mucus sensations and characteristics. Be specific and avoid general terms like tacky or stretchy. Use any words that you think best describe what you are observing. If the mucus is about the same from one day to the next, use the same word(s) to describe it. If it differs, create a new Mucus Description and record that instead.
  2. A Basic Infertile Pattern is established after 14 days of unchanging mucus.

Supporting Medical Evidence


  • "The effectiveness of a fertility awareness based method to avoid pregnancy in relation to a couple’s sexual behavior during the fertile time: a prospective longitudinal study," Frank Hermann et al. Hum. Reproduction. 2007;22(5):1310-1319
  • "European multicenter study of natural family planning (1989–1995): efficacy and drop-out," The European Natural Family Planning Study Groups. Advances in Contraception (1999) 15: 69.
  • "Natural family planning with and without barrier method use in the fertile phase: efficacy in relation to sexual behavior: a German prospective long-term study." Frank-Herrmann P, Freundl G, Gnoth C, et al. Adv Contracept. 1997;13:179–189
  • "About the dependability of the temperature method to avoid conception," Doering, Deutsche medizinische Wochenschrift 92: 1055-196, 9 Jun 1967
  • "Cycle characteristics after discontinuation of oral contraceptives," Gnoth et al Gynecol Endo. 2002; 16:307
  • "Timing of sexual intercourse in relation to ovulation," Wilcox et al, New England Journal of Medicine 1995; 333, 23:1517-5121
  • Natural Conception Regulation, Roetzer, Freiburg: Herder, 2006
  • "A prospective sympto-thermal trial in Austria, Germany and Switzerland," Roetzer, Presentation III International Congress IFFLP/FIDAF, Hong Kong, Nov 20-30, 1983
  • "Fertility awareness-based methods of family planning: A review of effectiveness for avoiding pregnancy using SORT," Manhart MD, Duane M, Lind A, Sinai I, Golden-Tevald J. Osteopath. Fam. Phys. 2013; 5:2-8.