--- title: "How Memory Chat Keeps Your Notes Private with Zero-Knowledge Encryption" description: "How Memory Chat encrypts your notes and files on your device, so only you hold the keys that can open them." locale: "en" canonical: "https://memorychat.app/en/blog/secure-note-taking-zero-knowledge-encryption/" publishedDate: "2026-08-11T09:47:51.253Z" updatedDate: "2026-10-16T23:11:26.000Z" author: "Memory Chat Team" tags: ["simple planner app","ADHD planner app","productivity","best second brain app"] readingMinutes: 4 --- # How Memory Chat Keeps Your Notes Private with Zero-Knowledge Encryption > How Memory Chat encrypts your notes and files on your device, so only you hold the keys that can open them. - **Published**: 2026-08-11 - **Author**: Memory Chat Team - **Canonical Article**: https://memorychat.app/en/blog/secure-note-taking-zero-knowledge-encryption/ - **Website**: https://memorychat.app --- A notes app often ends up holding more than notes. Next to your shopping lists there may be private thoughts, work documents, personal photos, and links you can't afford to lose. That's why choosing one is about **security and privacy** as much as convenience. In **Memory Chat**, your data belongs to you. We use **zero-knowledge encryption**, which keeps your information private even from us. ## What zero-knowledge encryption means Think of a safe where you hold the only key. The company that built the safe can't open it, and neither can the company that stores it for you. **Memory Chat** encrypts your private content **before it leaves your device**. Only the right keys can decrypt it, and the Memory Chat team doesn't have them. ### How it compares with other kinds of encryption The terms get used loosely, so it helps to separate them by where the data is and who can read it: - **Encryption in transit** protects data while it travels between your device and a server - **Encryption at rest** protects data while it's stored on the server - **End-to-end encryption (E2EE)** means only the sender and the intended recipient can read a message - **Zero-knowledge encryption** goes further: the company never holds the decryption keys, so it couldn't read your data even if it wanted to ## How your data is protected in the app Memory Chat encrypts your notes, images, files, recordings, checklists, budgets, and saved locations. The encryption happens on your device, before anything is synced to the service. What's stored is unreadable without the correct key, and when you open something, an authorized device decrypts it locally. ## How it works technically Each piece of encrypted content has its own key, and those keys are protected by a single **Master Key**. Your devices use them to decrypt the notes and files you have access to. **We don't store the Master Key on our servers.** It stays in protected storage on your device or in your account's recovery services: - **Secure Storage** on Android - **Apple Keychain / iCloud Keychain** on iPhone and iPad - **Google Drive**, when backup is enabled The result is that we can't read your data, even if we wanted to. ## What happens if the servers are hacked? Someone who broke into the servers would find files they can't use. Without your private key, the stored content stays unreadable. ## How this differs from most notes apps Most traditional note-taking apps encrypt data in transit and at rest, but the company often keeps the encryption keys. That can leave a way for user data to be accessed in some situations. With **Memory Chat**, the company never receives your decryption key. That was a deliberate design choice: our servers can't read your private content because they don't have the keys needed to decrypt it. ## You don't have to do anything differently Encryption runs in the background, so you use the app the same way you always would. You can still take notes and save photos and files, make checklists and manage budgets, save locations, share notes, add reminders, and work without an internet connection. ## On the device itself: biometric lock Zero-knowledge encryption protects your notes on their way to our sync servers and while they're stored there. It doesn't help if someone picks up your phone while it's unlocked. For that, Super Memory and Ultra Memory include a **biometric app lock**. You can protect the whole app with **Face ID**, **Touch ID**, or an **Android fingerprint**, and set it to lock straight away, so private notes, budgets, and personal reflections stay closed even when someone borrows your phone. ## Local-first storage If your internet drops, an app that keeps your notes on a server can leave you staring at a loading screen. Memory Chat keeps an indexed SQLite database on your phone, so your notes are stored there first, encrypted, and open with or without a connection. Our guide to the [best offline note-taking apps](/en/blog/best-offline-note-taking-app/) explains how that works in more detail. ## Summary We can't read your notes, because the keys that decrypt them stay with you. Your data is stored in SQLite on your device, so it's 100% available offline. On Super and Ultra you can add Face ID or a fingerprint lock. And you can start on the free Basic plan with 2-device sync, or move to Super or Ultra Memory, with prices adjusted for [Purchasing Power Parity (PPP)](/en/). If you're setting up a system around your notes, read how to build a [second brain without the overwhelm](/en/blog/best-second-brain-app/), or see how our sync compares with [Obsidian Sync](/en/blog/obsidian-sync-vs-memory-chat/). If you want notes that only you can read, **[get started with Memory Chat](/en/)**.