MarkDown Editor

A native Windows Markdown editor and viewer, fully portable and offline, with a reading experience inspired by Claude.ai's clean typography and layout.

Version française : README.fr.md

Features

• Reading mode: full Markdown/GFM rendering (headings, bold, italic, strikethrough, ordered/unordered lists, task lists, block quotes, tables, links, thematic breaks) rendered natively as a WPF FlowDocument — no embedded browser or HTML engine.
• Light / dark theme, manual toggle or automatic, following the Windows system theme.
• Open Markdown files directly by double-clicking a .md file once the file association is registered (see below).
• Open / Save / Save as, with native Windows dialogs.
• Bilingual interface (English / French), auto-detected from the system language at first launch.
• 100% portable: a single self-contained folder, no installer, no registry writes beyond the optional file association.
• 100% offline: no network request is ever made, no telemetry.

Requirements

• Windows 10 or Windows 11, 64-bit (x64).
• No .NET installation required — the application is published self-contained.

Getting started

1. Download or copy the MarkDownEditor folder anywhere you like, including a removable drive.
2. Run MarkDownEditor.exe.
3. Use Open to load a .md file, or associate .md files with the application (see below) to open them directly from Windows Explorer.

File association (optional)

MarkDown Editor never modifies the system without your consent. To associate .md files with the application so double-clicking opens them directly:

1. Open PowerShell in the scripts folder.
2. Run register-file-association.ps1.

This only writes to your user registry hive (HKCU) — no administrator rights are required, and nothing is installed system-wide. To undo this, run unregister-file-association.ps1.

Building from source

Requirements: .NET 10 SDK, Windows 10/11 x64.

scripts/build-portable.ps1

This produces a self-contained, portable build under build/ (or the output folder configured in the script), ready to copy anywhere.

License

MarkDown Editor is distributed under the GNU General Public License v3.0 (GPL-3.0-or-later). See LICENSE / COPYING at the repository root, and THIRD_PARTY_NOTICES.md for third-party dependency licenses.

Contact

• Website: https://patrickjaillet.github.io/MarkDown-Editor
• Email: sandefjord.development@proton.me