Estimate likely timing from the details you enter.Medical and safety information
Medical Disclaimer
PeriodlyWise provides period tracking, ovulation tracking, fertility-window estimation, and irregular-cycle awareness tools for personal education and cycle awareness. Our tools are designed to help users understand possible timing patterns based on the information they enter, including period start dates, average cycle length, period length, cycle regularity, and saved cycle history.
PeriodlyWise does not provide medical advice. Our tools do not diagnose medical conditions, confirm ovulation, confirm pregnancy, provide contraception guidance, provide fertility treatment, or replace care from a qualified healthcare professional. The calculations, reports, date ranges, reminders, and educational explanations shown by PeriodlyWise are estimates. They may be useful for personal tracking, but they are not guaranteed to be medically accurate for every person, every cycle, or every health situation.
The Pregnancy Calculator provides educational estimates of gestational age and due date, along with a week-by-week development guide.
Last updated: November 7, 2026
PeriodlyWise is for personal tracking and education only.
Our tools are not intended to be used as medical advice, diagnosis, treatment, contraception guidance, emergency guidance, fertility treatment, pregnancy confirmation, ovulation confirmation, or a substitute for a doctor, clinician, gynecologist, fertility specialist, or other qualified healthcare professional.
If you have severe pain, very heavy bleeding, fainting, dizziness, shortness of breath, suspected pregnancy complications, sudden cycle changes, or any urgent health concern, seek medical attention immediately.
Table of contents
Important medical noticeEstimates onlyNo medical adviceNo clinician relationshipNot for emergenciesNot a diagnosis toolTracker-specific limitsNot contraception guidanceNot pregnancy confirmationPregnancy CalculatorNot fertility treatmentData entry responsibilityFactors that can affect timingAge, life stage, and health differencesReports and saved historyWhen to seek medical adviceUser responsibilityChanges to this Medical Disclaimer
1. Estimates only
PeriodlyWise estimates period dates, ovulation timing, fertile windows, and irregular-cycle patterns from the details you provide. These estimates are based on general cycle timing logic and the data entered into our tools. For example, our Period Tracker may estimate your next period by using your last period start date, your average cycle length, your average period length, and your selected cycle regularity. Our Ovulation Tracker may estimate likely ovulation timing by working from your estimated cycle timing. Our Fertility Window Tracker may show a broader fertile window around likely ovulation timing. Our Irregular Period Tracker may use saved period records to compare cycle gaps and project wider windows.
These estimates are not promises. They are not clinical findings. They are not medical test results. A period may arrive earlier or later than expected. Ovulation may happen earlier or later than estimated. A fertile window may be different from the window shown by our tool. Irregular cycles may continue to change even after several months of saved history.
Guarantee medically exact dates for every user.PeriodlyWise uses ranges because cycle timing can naturally vary. A range is more honest than pretending that one exact date is guaranteed. When our tool shows a wider range, it is acknowledging uncertainty rather than claiming that something is necessarily wrong.
2. No medical advice
The information provided by PeriodlyWise is educational and informational. It should not be used to make medical decisions without consulting a qualified healthcare professional. Our tool does not evaluate your full medical history, symptoms, medications, lab results, pregnancy status, hormonal profile, contraception use, fertility history, or personal risk factors.
Because PeriodlyWise does not know your full health situation, our estimates cannot replace professional medical judgment. You should not delay medical care, avoid medical care, start or stop medication, change contraception, begin fertility treatment, or make pregnancy-related decisions based only on PeriodlyWise results.
If you have a health concern, speak with a qualified healthcare professional. If professional advice conflicts with a PeriodlyWise estimate, rely on professional advice.
3. No doctor-patient or clinician-patient relationship
Using PeriodlyWise does not create a doctor-patient relationship, clinician-patient relationship, therapist-patient relationship, fertility-specialist relationship, or any other healthcare provider relationship. PeriodlyWise is not a healthcare provider. PeriodlyWise does not examine users, provide individualized medical opinions, prescribe treatment, order medical tests, interpret lab results, or provide clinical follow-up.
Any information shown in our tools, reports, reminders, explanations, cards, downloadable summaries, or educational pages is general information only. Even if the information feels personally relevant because it uses your entered dates, it remains an estimate generated from limited data.
4. Not for emergencies
PeriodlyWise is not an emergency service. Our tools should not be used in urgent or emergency health situations. We cannot monitor symptoms, detect emergencies, contact emergency services, or determine whether your situation requires urgent care.
Seek immediate medical help if you experience symptoms including, but not limited to:
Urgent symptoms
- severe pelvic or abdominal pain
- very heavy bleeding
- fainting or severe dizziness
- shortness of breath or chest pain
- fever with pelvic pain
Pregnancy-related concerns
- severe pain during pregnancy
- suspected miscarriage
- suspected ectopic pregnancy
- bleeding during pregnancy
- symptoms that feel unusual or urgent
If you believe you may be experiencing a medical emergency, contact local emergency services or go to the nearest emergency department.
5. Not a diagnosis tool
PeriodlyWise cannot diagnose health conditions. A cycle tracking pattern may be useful to discuss with a clinician, but it is not a diagnosis by itself. Our tool cannot determine the cause of pain, missed periods, unusual bleeding, irregular cycles, discharge, fertility concerns, or pregnancy-related symptoms.
PeriodlyWise cannot diagnose or rule out conditions including, but not limited to:
| Area | Examples of conditions or situations our tool cannot diagnose |
|---|---|
| Pregnancy and bleeding | pregnancy, miscarriage, ectopic pregnancy, abnormal uterine bleeding, anemia |
| Hormonal and cycle conditions | PCOS, thyroid disorders, perimenopause, menopause, hormonal disorders, medication side effects |
| Reproductive health | endometriosis, fibroids, ovarian cysts, infertility, infections, pelvic inflammatory disease |
| Other concerns | sexually transmitted infections, reproductive cancers, complications from contraception, causes of severe pain |
If your periods are very painful, unusually heavy, absent, unpredictable, or suddenly different from your normal pattern, professional evaluation may be appropriate.
6. Tracker-specific limitations
Each PeriodlyWise tool has a different focus, but every tool has limits. Our Period Tracker estimates likely period timing from your last period date, average cycle length, average period length, and cycle regularity. If these details are incorrect, guessed, outdated, or incomplete, the estimate may be less useful. Even when your details are accurate, your next period may still arrive earlier or later than the projected date.
Our Ovulation Tracker estimates likely ovulation timing. It does not confirm that ovulation happened. Ovulation can shift from cycle to cycle, especially with irregular cycles, postpartum cycles, cycles affected by hormonal contraception, cycles affected by illness or stress, and cycles where ovulation is delayed. If confirming ovulation is important to you, you may need additional methods such as ovulation predictor tests, basal body temperature tracking, cervical mucus observations, ultrasound monitoring, blood tests, or clinical guidance.
Our Fertility Window Tracker estimates a likely fertile window. It does not confirm fertility, infertility, ovulation, pregnancy chances, or reproductive health status. A calendar estimate may show a window that is earlier, later, shorter, or longer than your actual fertile window.
Our Irregular Period Tracker uses saved period records to compare cycle gaps and estimate possible future windows. This history-based approach may be more useful than relying on one average cycle length, but it is still limited. Irregular cycles can change in ways that past records cannot fully predict.
7. Not contraception guidance
PeriodlyWise should not be used as the only method for avoiding pregnancy. Our tools do not provide contraception advice. Our estimates are not reliable enough to determine safe days, confirm infertility, or replace a contraception method recommended by a healthcare professional.
Ovulation timing can shift unexpectedly, even in people who usually have regular cycles. Because pregnancy risk depends on many factors, calendar-based estimates should not be treated as guaranteed contraception. If you want to avoid pregnancy, speak with a qualified healthcare professional about contraception options that are appropriate for your health, needs, and preferences.
8. Not pregnancy confirmation
PeriodlyWise cannot confirm whether you are pregnant. A missed period may happen for many reasons, including pregnancy, stress, illness, hormonal changes, contraception changes, breastfeeding, perimenopause, weight changes, thyroid conditions, PCOS, or other health factors.
If you think you may be pregnant, consider taking a pregnancy test and contacting a qualified healthcare professional when appropriate. If you have pain, heavy bleeding, dizziness, fainting, or bleeding during pregnancy, seek medical attention promptly. PeriodlyWise estimates should not be used to confirm or rule out pregnancy.
Pregnancy Calculator
The calculator estimates how far along you are on the date shown and when you reach 40 weeks. The estimated due date does not predict the day of birth. A result cannot confirm pregnancy, establish where it is located or whether it is developing as expected, or diagnose a miscarriage, ectopic pregnancy or other complication.
What affects the estimate
- Last period. Use the first day of your last menstrual period and your usual cycle length. The cycle adjustment approximates ovulation timing. Irregular cycles or an uncertain period date can make the estimate less reliable.
- Ultrasound report. Use the scan date and the gestational age or due date stated in the report. The calculator cannot interpret images or measurements. A first-trimester dating scan is generally the most accurate ultrasound for dating. Size differences on a later scan can reflect growth.
- IVF transfer. Use the transfer date and embryo age on the day of transfer from your fertility clinic. Confirm the due date with the clinic.
- Known due date. Enter the due date established by your clinician. The calculator uses that date to estimate gestational age and show the timeline.
- Conception date. A date of sex does not establish when conception occurred. This estimate cannot establish an exact conception date or paternity. Gestational age conventionally includes time before conception.
- Period and scan comparison. This mode illustrates published ACOG dating criteria for an appropriate initial scan. A difference, an uncertain period date or a later scan can require clinical review. The result cannot decide whether to change an established due date.
Use the due date established by your maternity care team for medical decisions. If estimates differ or you are unsure about your inputs, ask your care team to confirm the date.
Weekly development, size and milestones
Baby illustrations represent broad stages. Fruit and vegetable comparisons, typical lengths and published fetal-weight ranges are general references. The weight chart uses population data from pregnancies with one baby. These visuals cannot measure your baby, give an individual growth percentile, assess twins or other multiples, or screen for a health condition.
Week and trimester labels, term categories, progress indicators and countdowns follow the estimated dates. Follow your care team’s schedule for scans, prenatal tests and appointments, and their guidance on care after the due date and timing of birth.
Saved, downloaded, printed and shared results
Saved cards, notes, downloads and printouts are personal records of an estimate as of the date shown. They cannot substitute for a scan report or a clinical record. Check the inputs and the date on a copy before sharing it, especially if your care team has revised your dates.
When to seek urgent care
Seek medical care right away if you have bleeding or fluid leakage during pregnancy, severe or persistent abdominal pain, fainting, chest pain, trouble breathing, a headache that won’t go away, vision changes, or a slowdown or stop in your baby’s usual movements. If you may be experiencing an emergency, contact local emergency services. Seek care based on your symptoms even when the calculator gives a result without a warning.
Clinical and educational references
9. Not fertility treatment
PeriodlyWise does not provide fertility treatment, infertility evaluation, reproductive endocrinology care, or pregnancy planning advice from a clinician. Our tools may help you organize cycle information and estimate possible timing, but fertility can be affected by many factors that our tools cannot evaluate.
These factors may include, but are not limited to, age, ovulation function, sperm health, fallopian tube health, uterine health, hormone levels, medical history, medications, prior pregnancies, surgeries, infections, and other personal health factors. If you have fertility concerns, irregular cycles, known reproductive health conditions, repeated pregnancy loss, or questions about trying to conceive, speak with a qualified healthcare professional.
10. Data entry responsibility
PeriodlyWise results depend on the information you enter. If the entered dates, cycle lengths, period lengths, regularity choices, or saved records are incorrect, the estimates may be incorrect. If records are missing, incomplete, or entered late, the Irregular Period Tracker may have less context.
| If the entered data is wrong | The estimate may be affected |
|---|---|
| Last period date is entered incorrectly | Next period estimate may shift. |
| Cycle length is guessed | Period and ovulation windows may be less useful. |
| Period length is inaccurate | Period end estimate may be wrong. |
| Cycle regularity is selected incorrectly | The range may be too narrow or too wide. |
| Saved records are missing | Irregular-cycle reports may show limited pattern visibility. |
PeriodlyWise can support tracking, but users are responsible for entering accurate information and interpreting estimates cautiously.
11. Factors that can affect cycle timing
Cycle timing can change for many reasons. PeriodlyWise cannot fully account for every factor that may affect your body. Factors may include, but are not limited to, stress, travel, illness, fever, sleep changes, major lifestyle changes, intense exercise, weight changes, eating pattern changes, medications, emergency contraception, hormonal contraception, stopping contraception, postpartum changes, breastfeeding, pregnancy, miscarriage, perimenopause, thyroid conditions, PCOS, endometriosis, uterine fibroids, chronic health conditions, surgery, infections, and other hormonal changes.
12. Age, life stage, and health differences
Cycle tracking may work differently depending on age, life stage, reproductive history, contraception use, and health background. A pattern that is expected for one person may not be expected for another person. PeriodlyWise does not personalize medical interpretation for every body, age group, diagnosis, medication, or reproductive stage. Our tool can organize dates and show estimates, but it cannot decide whether a specific pattern is medically normal for you.
Period timing may be less predictable soon after a first period, during postpartum recovery, while breastfeeding, after stopping hormonal contraception, during perimenopause, with irregular cycles, with certain hormonal or reproductive conditions, during periods of illness, or during major stress. In these situations, a calendar estimate may be less useful because the body may not follow the same timing from one month to the next.
If you are unsure whether your cycle pattern is expected for your age, life stage, contraception status, postpartum status, fertility goals, or medical history, speak with a qualified healthcare professional. Our tracker can help you prepare a clearer record of dates and patterns for that conversation, but our tool should not be treated as the clinical interpretation of those patterns.
13. Reminders, reports, and saved history
PeriodlyWise may provide reminders, calendar-style timing suggestions, downloadable summaries, printed reports, shared summaries, saved records, and history-based reports. These features are intended to support personal tracking. They are not medical records, clinical reports, test results, diagnostic documents, or clinician-created summaries.
A reminder that your period may be approaching does not guarantee your period will start on that date. A reminder about ovulation or fertile timing does not confirm ovulation or fertility. A downloaded PeriodlyWise report may be useful as a personal note or conversation aid, but it should not be treated as a medical conclusion.
Saving records may make the tool more useful, but saved history still cannot guarantee future cycle timing. Users should review saved records for accuracy and delete incorrect entries when appropriate. Incorrect records can affect future estimates.
14. When to seek medical advice
Speak with a qualified healthcare professional about persistent or worrying symptoms, missed periods, unusual cycle changes, bleeding between periods or after sex, or fertility concerns. For urgent symptoms or suspected pregnancy complications, follow the emergency guidance above and seek care immediately.
The signs and situations listed above are examples only and may include, but are not limited to, the concerns described here. If you are worried about your health, seek guidance from a qualified healthcare professional.
15. User responsibility and limitation of reliance
By using PeriodlyWise, you understand that our tools provide estimates only, cycle timing can vary, results may be inaccurate, our tools do not replace medical care, our tools should not be used for emergencies, our tools should not be used as the only method to avoid pregnancy, our tools do not confirm ovulation or pregnancy, saved reports are not medical records, and health decisions should be made with qualified medical guidance.
You should not rely solely on PeriodlyWise for medical, reproductive, pregnancy-related, contraception-related, fertility-related, or emergency decisions. PeriodlyWise is intended to support awareness, not replace professional care. Any action you take based on PeriodlyWise estimates is taken at your own discretion and risk.
If PeriodlyWise shows an estimate that appears inconsistent with your symptoms, test results, clinician advice, or personal health situation, do not treat the estimate as more reliable than medical guidance.
16. Changes to this Medical Disclaimer
PeriodlyWise may update this Medical Disclaimer from time to time. Updates may reflect changes in our tools, features, content, legal requirements, or the way we explain limitations. The Last updated date at the top of this page shows when this Medical Disclaimer was most recently revised.
Continued use of PeriodlyWise after changes are posted means you understand and accept the updated Medical Disclaimer. By using PeriodlyWise, you acknowledge that our tools are designed for personal tracking and education only. You understand that period dates, ovulation timing, fertile windows, and irregular-cycle projections are estimates and may not be medically accurate for your individual situation.
You also understand that PeriodlyWise does not provide medical advice, diagnosis, contraception guidance, fertility treatment, pregnancy confirmation, ovulation confirmation, or emergency care. For personal medical concerns, unusual symptoms, pregnancy-related questions, fertility concerns, contraception decisions, or urgent health issues, please speak with a qualified healthcare professional.
This Medical Disclaimer should be read together with the context shown throughout PeriodlyWise, including the reminder that our calculators are designed to support awareness, not certainty. When a result appears precise, such as a calendar date or narrow timing window, it is still an estimate created from limited information. Users should treat every PeriodlyWise result as one helpful reference point, not as the final authority on their health, fertility, pregnancy status, symptoms, or medical care.