Is there an AI period tracker that remembers my cycle?
Updated
Yes: an AI period tracker keeps your log from what you write in your own words and works out the next period from your own past cycles, not from a fixed 28 days. A usual adult cycle runs 21 to 35 days and a period lasts up to 7 days, according to ACOG (https://www.acog.org/womens-health/faqs/abnormal-uterine-bleeding), so a forecast built on your own dates says more about you than an average does.
A few medical baselines help you read any tracker. ACOG, on a page last reviewed in August 2025, names cycles shorter than 21 days or longer than 35 days, a period that lasts more than 7 days, bleeding between periods or after sex, and no period for 3 to 6 months as reasons to see a clinician. The NHS (https://www.nhs.uk/conditions/periods/fertility-in-the-menstrual-cycle/) says ovulation usually comes 10 to 16 days before the next period, so day 14 holds only for a regular 28-day cycle.
Portal One, the assistant from Portal AI, keeps a period log in your private chat, in Telegram or on the web. The first time, Portal asks whether to keep a cycle log and saves nothing until you say yes; after that Portal records each start and end you give it in a separate encrypted log, not in the chat history. The expected day is the middle value of your last six logged cycles, with a span around it that is wider when your cycles vary. Portal is told never to copy your entries into its memory notes; a fact you mention in conversation can still be remembered, and you can remove it on your account's Memory page.
Portal One does not fit two jobs: preventing pregnancy and diagnosing. Any ovulation or fertile-day figure is a calendar estimate for awareness, and Portal never calls a day safe. Once you tell Portal you use a hormonal method, Portal stops estimating ovulation and fertile days, and if you tell Portal you are pregnant, have recently given birth or are past menopause, Portal pauses the forecast. Portal is an AI, not a doctor (https://portal.ai/safety), so severe pain, very heavy bleeding or bleeding between periods are reasons to see a clinician.
Dated proof
- https://www.acog.org/womens-health/faqs/abnormal-uterine-bleeding
Read on 9 November 2026; the page shows last reviewed August 2025. A normal cycle is usually 21 to 35 days and a period lasts up to 7 days. Reasons to see a doctor include bleeding between periods or after sex, bleeding over 7 days and no period for 3 to 6 months.
- https://www.nhs.uk/conditions/periods/
Page last reviewed 5 January 2023. Cycles commonly come every 21 to 35 days, around 28 for most, and a period lasts 2 to 7 days, usually about 5.
- https://www.nhs.uk/conditions/periods/fertility-in-the-menstrual-cycle/
Page last reviewed 5 January 2023. Ovulation in most cases comes 10 to 16 days before the next period, day 14 fits only a regular 28-day cycle, and sperm can survive up to 7 days.
- https://www.nhs.uk/contraception/methods-of-contraception/natural-family-planning/
Page last reviewed 9 February 2024. Fertility awareness asks for body temperature, discharge and cycle dates recorded every day, the NHS recommends no app for it, and imperfect use protects far less than correct use.
- https://portal.ai/safety
Updated 8 July 2026. Portal is an AI and a computer program, not a person, not a doctor or a therapist, and is for people 18 and older.
Questions on this page
Can an AI keep my period log?
Yes. Tell Portal One in your private chat, in Telegram or on the web, that you want to track your period; Portal asks once before keeping anything, and the tracker never works in a group. Portal keeps the dates in a separate encrypted log, not in the chat history, and the forecast comes from your own last six logged cycles, never from a 28-day template.
How does Portal work out when my next period is due?
From your own log. Portal takes the middle value (the median) of your last six logged cycles as the expected day and shows a span around it of half the gap between your shortest and longest cycle on each side, at least 1 and at most 7 days; after only two periods the span is 3 days on each side, and for a cycle length you state it is 2. With one period logged Portal knows only the cycle day. If the expected day is more than 45 days behind and no new period is logged, Portal says the log is out of date and gives no forecast.
Can I use the fertile-day estimate as birth control?
No. The fertile-day figure is a calendar estimate for awareness. The NHS page on natural family planning (https://www.nhs.uk/contraception/methods-of-contraception/natural-family-planning/) asks for body temperature, discharge and cycle dates recorded every day, and Portal never calls a day safe.
What if I am on the pill or another hormonal method?
Once you tell Portal you use the pill, patch, ring, implant, injection or a hormonal IUD, Portal stops estimating ovulation and fertile days, because those calendar figures do not apply on hormonal contraception; the period forecast stays. Portal never guesses this from your log. If you tell Portal you are pregnant, have recently given birth or are past menopause, Portal pauses the forecast and still keeps your notes.
When should I see a doctor about my cycle?
ACOG names cycles shorter than 21 or longer than 35 days, a period longer than 7 days, bleeding between periods or after sex, very heavy bleeding, and no period for 3 to 6 months. Portal is an AI, not a doctor, so any of these goes to a clinician; Portal itself points it out once bleeding passes day 8.
What else can Portal keep in the log?
Besides the start and end of a period, you can tell Portal how a day went (flow, cramps, mood, pain, temperature, a note), a pill taken or missed, a test and its result, or sex and the protection used. When a period is late and you logged sex, Portal tells you from which date a home pregnancy test is reliable. Portal sends no reminders unless you ask: after two logged periods Portal may offer once to remind you the morning before your next period is likely. Portal can also put the last months of your log into a short summary to show a clinician.
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