Cosmicore

A Period Tracker for Your PC

guide

a period tracker for your PC.

almost every period tracker is a phone app with a server behind it. if you’d rather keep your cycle on your own computer — a file, not an account — this page is the short version of how.

why a desktop tracker at all

a phone app follows you everywhere, and so does its cloud. a desktop tracker sits where you left it. there’s no account to create, no sync to trust, and nothing leaves the machine. if you journal at a desk anyway — or you’d just rather your cycle didn’t live on a phone that crosses borders and gets lost — the desktop is the quiet option.

what to look for

offline by design
not an app that “works offline” and syncs later — an app with no server at all. if the company’s privacy page can’t say where the data lives in one sentence, it lives on their computers, not yours.
a file you can see
your data should be a file you can find, copy, and back up yourself. if you can’t export everything, you’re renting it.
a way to own it
you should be able to buy software outright and keep it — not be forced to rent it by the month. Cosmicore apps are a one-time purchase you own.
no analytics
a tracker that tracks you back is a bad joke. a 2025 study in BMC Women’s Health looked at 14 menstrual apps and found 71.4% of them shared data with third parties.

where LunaLog fits

LunaLog is our answer to that list: an offline period tracker for Windows, macOS, and Linux — cycle calendar, weekly planner, and journal in one app, with everything stored in a local file you own. it never connects to the internet because there is nothing to connect to.

see LunaLog → can period-tracker data be subpoenaed? →

last updated September 2026.