7 Private Period Tracker Apps That Never Upload Your Data (2026) — With Verification Guide
After the $59.5 million Flo settlement, millions of women are looking for period trackers that actually keep data private. Here are the seven best options — and a 3-minute test to verify any app's privacy claims yourself, without trusting anyone's word for it.
Most period tracking apps upload your data to their cloud servers. They promise to keep it safe. Some of them keep that promise. But as the Flo Health lawsuit showed — a $59.5 million settlement involving Google, Flo, and Flurry — promises are not always kept, and intimate health data is extraordinarily valuable to advertisers.
A different category of period tracker exists: apps that store all data in your device's local storage. These apps physically cannot share your data because they never receive it. In this article we review the seven best options, starting with how you can verify any app's privacy before trusting it with your most intimate health information.
First: How to Verify If Any Period App Is Truly Private (3-Minute Test)
Before trusting any app's privacy claims, run this test. It works on any web or browser-based period tracker in Chrome, Firefox, or Edge.
Open the app in a desktop browser
Navigate to the period tracker's web app in Chrome or Firefox. Open Developer Tools with F12 (Windows) or Cmd + Option + I (Mac).
Go to the Network tab, filter by Fetch/XHR
In the DevTools panel, click the "Network" tab. Click "Fetch/XHR" to show only data requests. Click the clear button to remove any pre-existing requests.
Log a symptom or period day
Inside the period tracker, log something real — a period start date, a symptom, or a mood entry. This is the action that would trigger a server upload if the app uses cloud storage.
Watch the Network tab
If the app is truly local-only: the Network tab stays empty. If the app is cloud-based: rows appear, with requests going to the app's backend servers. A cloud-based app cannot hide this — the browser always shows outbound requests.
Check Local Storage directly
In DevTools, go to Application → Local Storage → [your domain]. A truly local app shows your data stored here — on your device only.
This DevTools test only works for web or browser-based apps. For native apps, check: Does it work offline with no internet connection? Does the privacy policy say "local storage only"? Has it received an independent security audit? iOS apps that are truly local will work fully in airplane mode.
The 7 Best Private Period Tracker Apps in 2026
We tested each of these apps for privacy, features, device compatibility, and ease of use.
CycleVault
A web-based period tracker where all data is stored in browser localStorage. No account. No server. No email required. Accessible on any device — Android, iOS, desktop — through any browser. Passes the DevTools test: zero outbound requests when logging symptoms. The only private period tracker that works on Android.
Strengths
- Passes DevTools test: zero outbound requests
- Works on Android — most alternatives are iOS only
- No account or sign-up ever required
- One-click data export as JSON or CSV
- Import full history from Flo or Clue
- Free tier genuinely complete
Limitations
- Data tied to one browser (export to switch devices)
- Clearing browser storage deletes data
- Web app only — no native app install
Drip
Open-source period tracker with a strong privacy reputation. Stores all data on your device and has been independently verified by the privacy community. The code is publicly available for audit. Best open-source option for iOS users.
Strengths
- Open-source and fully auditable
- No ads, no tracking, no account
- Completely free
- Strong iOS UX
Limitations
- iOS only — Android users excluded
- Less polished than mainstream apps
- Fewer features — no pattern insights
Euki
Built with reproductive health privacy specifically in mind. Includes a "decoy password" feature — entering the wrong password opens a fake version of the app — for users who may face scrutiny of their health data. Best for users in states with restrictive reproductive laws.
Strengths
- Decoy password — unique safety feature
- Built by a reproductive rights organisation
- No data ever leaves the device
- Educational reproductive health content
Limitations
- iOS only
- More basic feature set
- Less accurate for irregular cycles
Embody
Open-source, privacy-by-default period tracker with European server hosting for users who want optional encrypted backup under GDPR jurisdiction. Local-first architecture means the app functions fully without any server interaction.
Strengths
- Local-first — works fully offline
- GDPR-compliant optional backup
- Good chronic illness tracking
- Open source
Limitations
- Smaller feature set
- Less active development
Periodical
A minimalist period tracker that stores everything locally. Best for users who want the absolute simplest interface — just period dates and cycle prediction. iOS only. Zero features beyond the essentials.
Bearable
Not a pure local-storage app — it uses cloud sync — but GDPR-compliant with European servers and a strong privacy policy. Particularly well-suited for users tracking chronic illness alongside their cycle. Worth considering if you need cross-device sync and are comfortable with cloud storage under EU protection.
Bearable uses cloud storage and does not pass the DevTools test. It is more private than Flo but not a local-only alternative. Choose this if cross-device sync is essential to you.
Clue
The strongest of the mainstream cloud-based trackers from a privacy standpoint. German-headquartered, GDPR-compliant, has not been involved in the Flo lawsuit, and has received better privacy scores from researchers. Still cloud-based — not local storage.
Clue does not pass the local-storage verification test. Your data lives on Clue's servers. It is a better option than Flo for users who want stronger privacy commitments, but it is not a local-storage alternative.
Side-by-Side Comparison
| App | Storage | Android | Verifiable | No Account | Free | Export |
|---|---|---|---|---|---|---|
| CycleVault | ✓ Local only | ✓ | ✓ DevTools | ✓ | Full | JSON/CSV |
| Drip | ✓ Local only | iOS only | Open source | ✓ | ✓ | Limited |
| Euki | ✓ Local only | iOS only | ✓ | ✓ | ✓ | — |
| Embody | ✓ Local-first | ✓ | Open source | ✓ | ✓ | — |
| Periodical | ✓ Local only | iOS only | Limited | ✓ | ✓ | — |
| Bearable | Cloud (GDPR) | ✓ | — | — | Limited | ✓ |
| Clue | Cloud (GDPR) | ✓ | — | — | Limited | ✓ |
What "Local Storage" Actually Means in Plain English
When we say an app uses "local storage," we mean your data is saved inside your device's own storage system — the same place your browser saves bookmarks or preferences. It never leaves your device. The company that made the app has no copy of it.
The technical mechanism for web apps is called localStorage — a browser API that lets websites save data on your device. When CycleVault calculates your next period date, it is happening in JavaScript running on your device, reading data from your device's localStorage. No server call is made at any point.
What About Cross-Device Sync?
This is the main trade-off of local storage. If your data is only on your phone's browser, it is not automatically available on your tablet or laptop. There are two ways around this:
- Manual export and import: Export your data as JSON on one device, import it on another. Takes about 60 seconds. CycleVault has one-click export built in.
- End-to-end encrypted optional sync: The gold standard — syncing data between devices encrypted with a key only you hold. CycleVault is building this feature.
Frequently Asked Questions
Which period tracker is safest for users worried about legal data requests?
Apps with local storage only — CycleVault, Drip, Euki — are the safest, because a subpoena or legal request cannot obtain data that does not exist on any server. No data means nothing to hand over. This is particularly relevant for users in US states with restrictive reproductive laws.
Is Clue safer than Flo?
Clue has a stronger privacy track record than Flo — it is GDPR-compliant, German-headquartered, and has not been involved in Flo's lawsuits. However, it is still cloud-based. For users who want local-only storage, it is not the right option.
Can I bring my Flo data history when I switch?
Yes, if you switch to CycleVault. Flo allows you to export your data as a file. CycleVault's import feature reads that file and populates your cycle history. See our guide on how to export and import your data.
Switch to CycleVault — Bring Your History With You
Import your Flo data in 60 seconds. No account. Verify the privacy yourself in DevTools.
Start Free at CycleVault →