SumizAI vs Leynir Notes

What Leynir Notes is

Leynir Notes is encrypted note-taking software for Windows, where all notes are stored in a local vault secured with AES-256-GCM encryption - no cloud, no account, no subscription. The application comes from Switzerland, a country with a strong tradition of protecting financial and personal data privacy, which is reflected in Leynir Notes's uncompromising approach to securing saved content. Support for biometric unlock through Windows Hello adds a convenient yet secure layer of access, combining a high level of encryption with fast, everyday use.

Key features and functionality

AES-256-GCM encryption is a cryptographic standard used in applications with the highest security requirements, guaranteeing that even with physical access to the disk, note content remains unreadable without the right key. The complete absence of any cloud dependency means all data stays solely on the user's computer, eliminating the risk of leakage through a hacked external provider's server or a misconfigured sync setup. The no-account, no-subscription model sets Leynir Notes apart from most modern note-taking apps, which typically require registration and recurring fees - the user pays once, installs the application, and uses it with no further financial obligations or need to log in. Support for Windows Hello lets the encrypted note vault be unlocked with a fingerprint or facial recognition, instead of typing a long password every time, significantly improving day-to-day comfort without sacrificing security.

Who it's for

Leynir Notes is aimed primarily at Windows users for whom the security and privacy of saved content are an absolute priority, outweighing the convenience of cloud sync offered by competing tools. Lawyers, therapists, journalists, and other people working with exceptionally confidential information choose Leynir Notes for its top-tier encryption standard and complete absence of any external cloud provider intermediary. People tired of the subscription model typical of most modern software appreciate a one-time fee with no recurring monthly or annual costs. Users of laptops and computers equipped with fingerprint readers or facial recognition cameras happily use the convenience of Windows Hello while retaining maximum data security.

Use cases

A lawyer keeping notes about confidential client matters uses Leynir Notes, confident that none of that information will ever leave their computer or reach an external provider's servers. A therapist keeping notes from sessions with patients chooses the local AES-256-GCM encrypted vault as a way to meet strict professional confidentiality requirements. An investigative journalist keeping notes on sensitive material uses the complete absence of any cloud dependency to minimize the risk of information leaking before publication. Someone who values fast access to their private entries without typing a password every time uses biometric unlock through Windows Hello, while retaining the full security of the encrypted data.

Pricing and business model

Leynir Notes runs on a one-time payment model, with no subscription and no free tier - the user pays once for a license and uses the application with no further financial obligations. This model, increasingly rare in modern software dominated by subscriptions, reflects Leynir Notes's philosophy of putting user independence above recurring revenue for the developer - an application purchased once remains the user's property, with no risk of losing access if payments stop.

Comparison with SumizAI

Leynir Notes and SumizAI operate in entirely different areas of digital work. Leynir Notes is a local, encrypted notepad with no integration with artificial intelligence, focused solely on maximum security of stored data. SumizAI, by contrast, is a platform enabling conversations with multiple AI providers at once, running in the cloud and unrelated to local storage of the user's files. Someone who values the privacy of their notes might use Leynir Notes as the primary place to store sensitive entries, and use SumizAI separately when they need AI help with less confidential tasks related to generating or analyzing content.

AI notes in a local, encrypted vault

People keeping sensitive ai notes from consultations with AI models on confidential topics in Leynir Notes appreciate that AES-256-GCM encryption provides the highest possible level of protection for such entries, unavailable in cloud-based note-taking tools. Because Leynir Notes runs entirely offline, with no account and no cloud, ai notes saved in the application are never exposed to the risk associated with a data leak on the external service provider's side. Biometric unlock through Windows Hello keeps access to accumulated ai notes fast and convenient for everyday use, despite the highest security standard applied to protect that data. Having no subscription also means access to saved ai notes can never be cut off due to an expired payment, a real risk with cloud notepads built around recurring fees.

What SumizAI is

A note-taking application built around a conversation with an AI model. You ask a question, the answer streams back, and the answers worth keeping become Markdown notes — filed into a vault that is a folder on your own disk.

A vault is a directory holding base.md, a generated table of contents up to six levels deep, and a notes/ folder with one .md file per note. Before a note is written it is checked against the ones already there, so the fourth note about the same idea gets merged instead of added. Links between notes are ordinary Markdown links to files that exist.

The model is never ours: you bring your own API key to one of seven providers — Anthropic, OpenAI, Gemini, Groq, OpenRouter, a local Ollama or your own server — and pay that provider directly. A question sends the table of contents plus at most five relevant notes within a 24,000-character budget, and the app shows you which five it used.

Every answer kept this way becomes one of these ai notes, ready to search again months later without hunting back through old chats.

Side by side

Where they differ

• AlternativeTo's description of Leynir Notes does not mention an AI model. That is the whole starting point in SumizAI: you have a conversation with a model on your own API key, and the answers worth keeping become notes without you filing them.
• Leynir Notes is paid software. Compare the two numbers directly: SumizAI is one dollar a month, one plan, and your AI provider bills you separately for the model you chose.
• AlternativeTo's description of Leynir Notes does not mention Markdown, so check what format your notes end up in before you fill it up. SumizAI writes standard .md files to a folder you picked, and an unpaid account can still export all of them.
• Leynir Notes advertises encryption. SumizAI answers the same worry a different way: on the desktop the notes never leave your disk, and the material a question sends to the model is capped at the table of contents plus at most five notes — and the app shows you which five it used.
• AlternativeTo lists no mobile version of Leynir Notes. SumizAI runs on macOS, Windows, iOS and Android.

Which one to pick