SEO Note 2.1 vs 1.3.34: which build to download

This site offers two programs under one name. SEO Note 2.1 is the current one and the one we develop — one code line that now runs on Windows, on Linux and, since 2.1, on Android. SEO Note 1.3.34 is the classic build, frozen at its last release, and still the right answer for machines 2.1 does not run on. Both keep your notes in files you own, work offline and need no account; the desktop line puts them in one SQLite file, the phone version in a folder of Markdown notes.

The short version: Windows 10 or 11, 64-bit, Linux x64 or Android 6.0 and newer → take 2.1. Windows 7, Windows 8 or a 32-bit system → take 1.3.34. Everything below is what that choice actually costs and gains.

Side by side

	SEO Note 2.1	SEO Note 1.3.34 (classic)
Systems	Windows 10 / 11 (64-bit), Linux x64 with a desktop, Android 6.0 and newer	Windows XP and later, 32-bit included
Download	127 404 042 bytes (~121 MB) installer; AppImage 146 121 320 bytes; .deb 112 837 524 bytes; APK 10 893 833 bytes	2 630 931 bytes (~2.5 MB)
On disk after install	about 460 MB on Windows (454 171 KB measured on the unpacked build), 366 873 KB declared by the .deb — that is the runtime, not your notes; the APK is a 10 MB download	9 134 800 bytes (8.7 MB) in 25 files, measured
What it is built on	Electron 44, plain JavaScript	native Win32 (MFC)
Data file	.seonote — one SQLite database	.seo — one OLE compound document
Note formats	Markdown, plain text, HTML, rich text	plain text, rich text, HTML
Development	active	finished; still downloadable
Account, cloud, telemetry	none required; sync is your own git repo, WebDAV or S3	none; the program never opens a network connection
Auto-update	no: 2.1.2 asks nothing and installs nothing. The 2.0.0 file used to query GitHub for a newer release, and that code is out of the current build	no
Code signing	desktop files unsigned, Android APK signed with our release key	not signed

What 2.1 has that 1.3.34 does not. The list below is the desktop program; on the phone the same interface and editor arrive, and the entries that need a database, a keyring or a local network socket answer with a named refusal instead of pretending.

• Password protection of the whole file and of single notes: AES-256-GCM with an Argon2id key, opt-in, and when a note is locked its text is removed from the search index instead of merely hidden.
• Markdown editing, wikilinks, tags, a graph view of the vault and version history per note.
• AI features that talk to a model you connect through any OpenAI-compatible server — a local Ollama or LM Studio, or a cloud one you pick. The key lives in the system keychain, and text goes only to the address you named.
• An MCP server, so an AI agent can read and edit your notes while the program runs.
• A web clipper: a token-protected receiver on 127.0.0.1 that a browser extension or script posts a selection to, plus a clipboard watcher.
• Optional sync of the one file through git, WebDAV or S3 — still no account and no service of ours.
• Import of other outliners: classic .seo, Evernote .enex, Google Keep JSON, TreePad and KeyNote .knt.
• Interface in English, Russian, Turkish and German; portable mode (a Data folder next to the program, ready for a USB stick).

What 1.3.34 still does better. It runs where 2.1 cannot: Windows 7, Windows 8, any 32-bit system, and machines where a few hundred MB of Electron runtime is too much. It is small and boring in the good way — a 2.5 MB download that installs 25 files. On the 2015-era Core i5 we measured it on, its window appeared in 2–3 seconds and the process sat at about 24 MB of memory with no network connections observed. If your work machine is old and your notes are already in a .seo file, there is no reason to move.

Both are the same idea. A tree of notes on the left, an editor on the right, files you own. 2.1 adds the parts that a native 2008-era Win32 app was never going to get: modern cryptography, Markdown, an AI that works locally, Linux, and now a phone build.

Your old .seo file. SEO Note 2.1 does not open .seo in place — it imports it. Importing reads the file without writing to it and appends the content into the .seonote file you currently have open, so the classic file stays intact as your backup. The tree, titles, created and modified dates, per-node text and background colors, bold / italic / underline / strike / grayed flags, read-only marks, checkbox states, icons, page tab colors, bookmark slots (Ctrl+0…9) and reminders carry over. Three things to know before trusting an important file: per-note view passwords are not carried (the note content is imported and you are warned), rich text is converted to Markdown and tables inside RTF are dropped, and the import of .seo is implemented and tested on Windows only — on Linux the message is to do the import on Windows and bring the resulting .seonote file across. Embedded objects such as pictures pasted into an HTML note are not read: 2.1 parses four streams of the compound file, and attachments are not among them.

How to try 2.1 without risking anything.

1. Copy your .seo file somewhere else first. The importer never writes to it, but a copy costs nothing and makes the experiment reversible.
2. Install 2.1, create a new empty file (the default lands in the app data folder, or pick your own path).
3. Import the .seo copy into it. Read the warnings the importer prints — they name what was converted and what was skipped.
4. Open the same file a week later and check the parts you actually rely on: search, the nodes you color, the bookmark slots.
5. Only then decide whether the classic build becomes your backup copy rather than your working program.

Honest limits of this page. The Windows disk figure is measured on the unpacked 2.1.2 build, the Linux one is what the released .deb declares, and the classic figures come from one machine (Core i5-5300U, 8 GB, Windows 10, SSD) — your numbers will differ. The desktop installers are unsigned, so SmartScreen warns; the Android APK is signed with our release key. The phone build exists and installs today, and it is a subset of the desktop program: no per-note history, no password or encryption, no sync, no clipper, no AI on it. A web version we do not have, and no one is coming to remove that limitation soon.

Download page with all three builds and their SHA-256 checksums · Migrating a .seo file to 2.1 · Version history · Quick start

Read also: OneNote alternative · vs Obsidian · Portable notes on Windows 7 · FAQ

Mini FAQ

Can I install SEO Note 2.1 and 1.3.34 on the same machine? Yes, they are separate programs with separate data files, and the classic build keeps working while you test 2.1. Do not point both at the same file: 2.1 reads .seo by importing it, which copies content into a .seonote file rather than opening it in place.

Will my notes look the same in 2.1 after importing a .seo file? The tree, note titles, dates, node colors, bold/italic/underline flags, read-only marks and bookmark slots carry over. Rich-text formatting is converted rather than copied pixel-for-pixel: RTF becomes Markdown and tables inside RTF are dropped, so give an important file a trial import before you rely on it.

Which build gets new features? Only 2.1. The classic 1.3.34 is finished: it is still downloadable and still opens your files, but nothing is added to it, and there is no upgrade patch for it — the upgrade path is 2.1.

Is either build signed or auto-updating? Partly, and we would rather say it than have you find it. The desktop installers have no code-signing certificate yet, so Windows SmartScreen warns on the first start of either one; the checksums on the download page let you verify what you got. The Android APK is signed with our release key, which is what lets a phone install upgrades of the same app instead of a second app. Nothing installs an update behind your back: updating means downloading a new installer here. One honest detail about the older 2.0.0 file — it asked GitHub, at startup and once a day, whether a newer release exists, and there is no feed for that question to find. The code is out of 2.1.2, so the current build asks nothing.

I run Linux. Is there a classic build for it? No. 1.3.34 is a 32-bit Windows program; Wine is not something we test or support. On Linux the only SEO Note is 2.1, as an AppImage or a .deb. One limitation matters for a first move: importing an old .seo file is implemented and tested on Windows only, so do the import there, then carry the resulting .seonote file to Linux.

So there is an Android build now — is it the same program? It is the same interface and the same editor, because the phone app reuses the desktop renderer, and it is a smaller program on purpose: notes are a folder of Markdown files in the app sandbox rather than one SQLite database, so per-note history, passwords and encryption, sync, the web clipper and the AI features answer there with a named refusal. The signed APK is 10 893 833 bytes and needs Android 6.0 or newer.