Do period tracking apps really sell your data?

Many monetize it in some form. A Privacy International review found the large majority of popular period and pregnancy apps shared data with third parties such as advertising and analytics companies, and the US Federal Trade Commission took action against Flo in 2021 over allegations it shared health information with outside firms despite its privacy promises. Not every app does this, and policies change — but it's common enough that you should check before you trust one.

What is the most private way to track my period?

Pen and paper is the most private of all. The closest digital equivalent is a tracker that stores everything locally on your device, requires no account, and loads no third-party trackers — so there is nothing to upload, sell, or subpoena. Period Tools' tracker works this way.

Does Period Tools sell or store my cycle data?

No. Our free tracker runs entirely in your browser and saves your log only in that browser's local storage. We never receive it, so we cannot sell, share, or hand it over — we can't sell what we never see. The trade-off is that your log lives on that one device unless you choose to back it up yourself.

What should I look for in a private period tracker?

Five things: on-device or end-to-end-encrypted storage; no account required to start; no third-party advertising or analytics trackers; a plain-English data policy that says it will not sell your data; and a clear business model (if it's free and the company isn't selling data, know how it actually makes money — for us it's ads and affiliate links on our calculators, never your cycle data).

Period trackers that don’t sell your data

Your cycle is some of the most personal data you have, and a lot of period apps treat it as a product to be shared or sold. If that bothers you — or the news about period-app privacy pushed you to look for something safer — this is a plain guide to what these apps actually collect, why it matters more since 2022, how to spot a genuinely private tracker, and a free one that keeps everything on your own device.

What period apps actually collect

A typical period app knows when you bleed, when you have sex, your moods, symptoms, medications, pregnancy attempts and outcomes — a remarkably detailed health picture. The problem isn’t the logging; it’s where that data goes. Privacy International’s testing found that the large majority of popular period and pregnancy apps it reviewed shared data with third parties such as advertising and analytics services. In 2021 the US Federal Trade Commission settled with Flo over allegations that it had shared sensitive health data with outside companies despite promising users it wouldn’t. Period-app data practices have stayed under regulatory and legal scrutiny since.

None of this means every app is reckless — Apple and Samsung’s built-in trackers, for example, are encrypted on your device, and some independent apps are explicitly privacy-first. The point is simply that “free” usually has a business model behind it, and with period apps that model has often involved your data.

Why this got more serious after Roe

After the US Supreme Court overturned Roe v. Wade in 2022, a wave of people deleted their period apps — an FTC study was even titled after that exact reaction. The worry is straightforward: data sitting on a company’s servers can, in principle, be requested through legal process, and cycle data can reveal a missed or ended pregnancy. Whatever your views, it made one thing obvious: data that never leaves your device can’t be handed over, because there’s no central copy to request. Privacy stopped being a nice-to-have and became a real selection criterion — people now choose trackers by how, and where, their data is stored.

How to spot a genuinely private tracker

On-device or end-to-end encrypted storage. Your log should live on your phone/computer, or be encrypted so even the company can’t read it.
No account required to start. If you must hand over an email and create a profile before logging a single day, your data is going somewhere.
No third-party ad/analytics trackers loading inside the tracker itself.
A plain-English policy that says, clearly, it will not sell your data — not buried in legalese.
An honest business model. If it’s free, know how it makes money. “We sell ads next to free tools” is very different from “we sell your cycle.”

How the Period Tools tracker is different

Our free period tracker is built around exactly those rules. It runs entirely in your browser and saves your log only in that browser’s local storage. There’s no account, no sign-up, and your cycle data is never sent to us — so we literally cannot sell, share, or be made to hand over what we never receive. We’re upfront about how we keep the lights on, too: the site makes money from ads and affiliate links on our free calculators, never from your data.

We won’t oversell it — there’s an honest trade-off. Because nothing leaves your device, your history lives on that one browser: clear your browser data or switch phones and it’s gone, and there’s no built-in cross-device sync today. For a lot of people that trade — total privacy in exchange for keeping your own backup — is exactly the point. If you ever want encrypted sync across devices, that’s the one thing we’d ask you to opt into deliberately, and it would stay encrypted so it keeps the same promise.

Track your cycle without handing it to anyone.

Open the free tracker

Frequently asked questions

Do period tracking apps really sell your data?: Many monetize it in some form. A Privacy International review found the large majority of popular period and pregnancy apps shared data with third parties such as advertising and analytics companies, and the US Federal Trade Commission took action against Flo in 2021 over allegations it shared health information with outside firms despite its privacy promises. Not every app does this, and policies change — but it's common enough that you should check before you trust one.
Can my period data be used against me legally?: It's a real concern that drove many people to delete their apps after the 2022 overturning of Roe v. Wade. Data held on a company's servers can, in principle, be requested through legal process. The most protective setup is data that never leaves your own device, because there is no central database for anyone to request.
What is the most private way to track my period?: Pen and paper is the most private of all. The closest digital equivalent is a tracker that stores everything locally on your device, requires no account, and loads no third-party trackers — so there is nothing to upload, sell, or subpoena. Period Tools' tracker works this way.
Does Period Tools sell or store my cycle data?: No. Our free tracker runs entirely in your browser and saves your log only in that browser's local storage. We never receive it, so we cannot sell, share, or hand it over — we can't sell what we never see. The trade-off is that your log lives on that one device unless you choose to back it up yourself.
What should I look for in a private period tracker?: Five things: on-device or end-to-end-encrypted storage; no account required to start; no third-party advertising or analytics trackers; a plain-English data policy that says it will not sell your data; and a clear business model (if it's free and the company isn't selling data, know how it actually makes money — for us it's ads and affiliate links on our calculators, never your cycle data).

Free Period Tracker — private, on-device, no account
How to track your period — what to log and the best methods
How accurate are period tracking apps?
Period tracker for teens — private tracking for new cycles, no account

— The Period Tools Team