Perimeter
Perimeter support
Last updated 15 September 2026.
Perimeter records perimenopause symptoms in one place, including the ones nobody connects to each other, shows where they turn up together, and turns a stretch of your own log into a script you can say out loud in a ten minute appointment.
Why it will not tell me what stage I am in
Perimeter never stages and never attributes. It will not say which phase of perimenopause or menopause you are in, will not put a symptom down to a hormone, and has no view on HRT.
Staging is a clinical judgement made against criteria this app cannot evaluate, and being wrong causes harm in both directions: someone told she is probably postmenopausal may stop using contraception on the strength of it.
So the cycle pattern is the one you chose for yourself and is never inferred from your log. Perimeter groups what you recorded next to what you told it. Only you and your clinician can work out the rest.
Why an analysis only describes, never explains
Findings are written as co-occurrence and nothing more: what you recorded alongside what else, with the figures. You will see a sentence shaped like "on days following fewer than six hours of sleep, you recorded higher brain fog", and never one that names a cause.
It will not diagnose, suggest a test, name a medication, or tell you things are improving or worsening. It looks for patterns across symptoms you may not have connected, such as ringing in the ears alongside waking at three in the morning. If your log is too thin to support a pattern, it says so rather than inventing one.
Why it says to log more days first
An analysis and a script each need at least seven days logged. Below that there is nothing to find, and a confident-looking finding built on three days is worse than no finding at all.
Logging a day
The symptom list is long on purpose, in five groups, and the last group is the ones nobody connects. You tap only what happened, then set a severity for those. Anything you do not tap means it did not happen that day, not that it was mild. You can also save a day as a clear day, record hours slept and a stress rating, and write a note.
The appointment script
Perimeter builds an opener, a short list of points and a few questions, in your own voice, first person, as sentences you can say out loud. The points are ordered by how much your log supports them and carry the counts, because a figure survives an interruption and a feeling does not. The questions are written so a busy clinician can answer them in a sentence.
It is meant to be printed or shared rather than read off a screen: a phone in an appointment reads as distraction, and looking things up mid-sentence is the moment you lose the thread. Nothing is added that you did not record, and it will not predict what your clinician will say.
The HRT question
Perimeter does not give medical guidance and has no view on whether HRT is right for you. It links out to the NICE public information on menopause, written for patients and kept current by clinicians, rather than restating it in our own words.
What Perimeter is not
- Not a medical device and not a diagnosis. It records what you tell it and describes what it sees.
- Not contraception guidance and not a fertility indicator.
- It reaches no clinician. No clinician view, no sharing and no household account: nothing goes to your doctor unless you take it.
- Not for urgent symptoms. Nothing here should delay contacting a clinician about something that worries you.
An internet connection is required.
Subscriptions
Perimeter is sold as a subscription through your Apple ID. The current price and billing period are shown on the purchase screen inside the app, which reads them from the App Store for your country rather than repeating a figure here.
Manage it at Settings › your name › Subscriptions. Cancelling stops the renewal and leaves the current period running to its end; we cannot cancel it for you. After a reinstall or a new device use Restore Purchases, and if it finds nothing, check you are signed in with the Apple ID that bought it. Apple is the merchant of record, so refunds are requested at reportaproblem.apple.com.
Your log
What you record here is information about your body, at a point in your life you may not have told anyone about, so this is specific rather than reassuring. There is no password; you sign in with a code sent to your email address. No name, date of birth, address, phone number or insurance detail is asked for, because the app has nowhere to put them, and every table checks your account against the owner of the row.
Logging a day on its own goes nowhere else. When you ask for an analysis or a script, the entries in that window are sent to be analysed, including severities, sleep and stress figures, and anything you wrote in a note. Nothing is sent until you ask for one of those two things.
Deleting your account
Deleting your account erases your profile, every day you logged, every analysis and every script, immediately and unrecoverably. Save anything you want to take to an appointment first.
Deleting the account does not cancel the subscription. That relationship is with Apple, and nothing this app can do will touch it, so cancel it in Settings first if you have not already. The full policy is at carrierpress.com/perimeter/privacy.
Contact
One person reads that, so a reply may take a few days.
Perimeter is published by Jeffrey L Carrier.